/*{{{ Includer.IncludeFiles(ctx, {[[C:\Projekty\r e p o\pali\src\main\pali.hpp]]}) ===*/
/*
  {   -- filePaths
    [[C:\Projekty\r e p o\pali\src\main\pali.hpp]],
  },
*/
#ifndef PALI_HPP
#define PALI_HPP

///
///
///
/*{{{ Includer.IncludeFiles(ctx, {[[C:\Projekty\r e p o\CommonLibrary_cpp\src\main\no_sillywarnings_please.h]]}) ===*/
/*
  {   -- filePaths
    [[C:\Projekty\r e p o\CommonLibrary_cpp\src\main\no_sillywarnings_please.h]],
  },
*/
// Based on no_sillywarnings_please, Copyright (c) Alf P. Steinbach, 2010.
// See https://alfps.wordpress.com/the-no_sillywarnings_please-h-file/ .
// Extra warnings added for /Wall.

#ifndef PROGROCK_CPPX_COMPILERSPECIFIC_MSVC_NOSILLYWARNINGSPLEASE_H
#define PROGROCK_CPPX_COMPILERSPECIFIC_MSVC_NOSILLYWARNINGSPLEASE_H

#ifdef _MSC_VER

// The following are real warnings but are generated by almost all MS headers, including
// standard library headers, so it's impractical to leave them on.
#pragma  warning( disable: 4619 )   // there is no warning number 'XXXX'
#pragma  warning( disable: 4668 )   // XXX is not defined as a preprocessor macro

// The following are pure sillywarnings:
#pragma warning( disable: 4061 )    // enum value is not *explicitly* handled in switch
#pragma warning( disable: 4099 )    // first seen using 'struct' now seen using 'class'
#pragma warning( disable: 4127 )    // conditional expression is constant
#pragma warning( disable: 4217 )    // member template isn't copy constructor
#pragma warning( disable: 4250 )    // inherits (implements) some member via dominance
#pragma warning( disable: 4251 )    // needs to have dll-interface to be used by clients
#pragma warning( disable: 4275 )    // exported class derived from non-exported class
#pragma warning( disable: 4347 )    // "behavior change", function called instead of template
#pragma warning( disable: 4355 )    // "'this': used in member initializer list
#pragma warning( disable: 4428 )    // MSVC 9: universal-character-name encountered in source
#pragma warning( disable: 4505 )    // unreferenced function has been removed
#pragma warning( disable: 4510 )    // default constructor could not be generated
#pragma warning( disable: 4511 )    // copy constructor could not be generated
#pragma warning( disable: 4512 )    // assignment operator could not be generated
#pragma warning( disable: 4513 )    // destructor could not be generated
#pragma warning( disable: 4610 )    // can never be instantiated user defined constructor required
#pragma warning( disable: 4623 )    // default constructor could not be generated
#pragma warning( disable: 4624 )    // destructor could not be generated
#pragma warning( disable: 4625 )    // copy constructor could not be generated
#pragma warning( disable: 4626 )    // assignment operator could not be generated
#pragma warning( disable: 4640 )    // a local static object is not thread-safe
#pragma warning( disable: 4661 )    // a member of the template class is not defined.
#pragma warning( disable: 4670 )    // a base class of an exception class is inaccessible for catch
#pragma warning( disable: 4672 )    // a base class of an exception class is ambiguous for catch
#pragma warning( disable: 4673 )    // a base class of an exception class is inaccessible for catch
#pragma warning( disable: 4675 )    // resolved overload was found by argument-dependent lookup
#pragma warning( disable: 4702 )    // unreachable code, e.g. in <list> header.
#pragma warning( disable: 4710 )    // call was not inlined
#pragma warning( disable: 4711 )    // call was inlined
#pragma warning( disable: 4820 )    // some padding was added
#pragma warning( disable: 4917 )    // a GUID can only be associated with a class, interface or namespace
#pragma warning( disable: 4996 )    // MSVC 9: a C std library function has been "deprecated" (says MS)

// Extra for /Wall:
#pragma warning( disable: 4350 )    // behavior change: 'member1' called instead of 'member2'
#pragma warning( disable: 4351 )    // new behavior: elements of array 'array' will be default initialized
#pragma warning( disable: 4464 )    // relative include path contains '..'
#pragma warning( disable: 4514 )    // 'function' : unreferenced inline function has been removed
#pragma warning( disable: 4718 )    // 'function call' : recursive call has no side effects, deleting
#pragma warning( disable: 5027 )    // 'type': move assignment operator was implicitly defined as deleted
#pragma warning( disable: 5045 )    // Compiler will insert Spectre mitigation for memory load if /Qspectre switch specified

#endif   // _MSC_VER

#endif   // PROGROCK_CPPX_COMPILERSPECIFIC_MSVC_NOSILLYWARNINGSPLEASE_H

/*}}}*/



///
///
///
/*{{{ Includer.IncludeFiles(ctx, {[[C:\Projekty\r e p o\CommonLibrary_cpp\src\main\disable_warnings.h]]}) ===*/
/*
  {   -- filePaths
    [[C:\Projekty\r e p o\CommonLibrary_cpp\src\main\disable_warnings.h]],
  },
*/
#ifdef _MSC_VER
#   pragma warning( push )
#   pragma warning( disable: 4100 )
#   pragma warning( disable: 4189 )     // 'identifier' : local variable is initialized but not referenced
#   pragma warning( disable: 4191 )
#   pragma warning( disable: 4242 )
#   pragma warning( disable: 4244 )
#   pragma warning( disable: 4267 )
#   pragma warning( disable: 4350 )
#   pragma warning( disable: 4365 )
#   pragma warning( disable: 4371 )
#   pragma warning( disable: 4548 )
#   pragma warning( disable: 4643 )
#   pragma warning( disable: 4647 )
#   pragma warning( disable: 4738 )
#   pragma warning( disable: 4774 )     // '<function>' : format string expected in argument <position> is not a string literal
#   pragma warning( disable: 4820 )
#   pragma warning( disable: 4987 )
#   pragma warning( disable: 5026 )
#   pragma warning( disable: 5027 )
#   pragma warning( disable: 5031 )     // #pragma warning(pop): likely mismatch, popping warning state pushed in different file
#   pragma warning( disable: 5219 )     // implicit conversion from 'type-1' to 'type-2', possible loss of data
#   pragma warning( disable: 5243 )     // 'type-name': using incomplete class 'class-name' can cause potential one definition rule violation due to ABI limitation
#endif

#ifdef __GNUC__
#   pragma GCC diagnostic push
#   pragma GCC diagnostic ignored "-Wpedantic"
#   pragma GCC diagnostic ignored "-Weffc++"
#   pragma GCC diagnostic ignored "-Wconversion"
#   pragma GCC diagnostic ignored "-Wsign-conversion"
#   pragma GCC diagnostic ignored "-Wshadow"
#   pragma GCC diagnostic ignored "-Wstrict-aliasing"
#endif

/*}}}*/

#ifdef UNDEF_NDEBUG
#undef NDEBUG
#endif

#include <cstddef>
#include <cassert>
#include <algorithm>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <memory>
#include <limits>
#include <iostream>

/*{{{ Includer.IncludeFiles(ctx, {[[C:\Projekty\r e p o\CommonLibrary_cpp\src\main\reenable_warnings.h]]}) ===*/
/*
  {   -- filePaths
    [[C:\Projekty\r e p o\CommonLibrary_cpp\src\main\reenable_warnings.h]],
  },
*/
#ifdef _MSC_VER
#   pragma warning( pop )
#endif

#ifdef __GNUC__
#   pragma GCC diagnostic pop
#endif

/*}}}*/



///
///
///
void noop(...) { }

///
///
///
#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))

///
///
///
#define NON_COPYABLE(C) \
    C(const C&) = delete; \
    C& operator=(const C&) = delete;

///
///
///
#define NON_MOVABLE(C) \
    C(C&&) = delete; \
    C& operator=(C&&) = delete;

///
///
///
#define NON_DESTRUCTIBLE(C) \
    ~C() = delete;

///
///
///
template<typename T>
void debug_echo(T x, const char* name, const char* delim, int line)
{
    std::cout
        << "DEBUG_ECHO   " << name << ": "
        << delim << x << delim
        << "   (line " << line << ")"
        << '\n';
}

///
///
///
#define DEBUG_ECHO(x) do { debug_echo(x, #x, "", __LINE__); } while (0)

///
///
///
#define DEBUG_ECHO_DELIM(x, delim) do { debug_echo(x, #x, delim, __LINE__); } while (0)



namespace pali {

///
///
///
typedef size_t umsize_t;
typedef ptrdiff_t msize_t;
typedef size_t umindex_t;
typedef ptrdiff_t mindex_t;
typedef ptrdiff_t munidiff_t;

const mindex_t Null_Index = -1;

const int Uninitialized_Positively = 7777777;
const int Uninitialized_Negatively = -Uninitialized_Positively;

}



///
///
///
#ifdef OVERRIDE_NEW_DELETE

namespace pali { namespace new_alloc {
    msize_t _allocated;
    msize_t _times;

    msize_t get_allocated()
    {
        return _allocated;
    }

    msize_t get_times()
    {
        return _times;
    }

    void clear_counters()
    {
        _allocated = 0;
        _times = 0;
    }
}}

void* operator new(size_t size)
{
    pali::new_alloc::_allocated += static_cast<pali::msize_t>(size);
    ++pali::new_alloc::_times;
    return malloc(size);
}

void* operator new[](size_t size)
{
    pali::new_alloc::_allocated += static_cast<pali::msize_t>(size);
    ++pali::new_alloc::_times;
    return malloc(size);
}

void operator delete(void* ptr) noexcept
{
    free(ptr);
}

void operator delete[](void* ptr) noexcept
{
    free(ptr);
}

#endif   // OVERRIDE_NEW_DELETE



namespace pali {

namespace alloc {

///
///
///
class Pool
{
public:
    Pool(msize_t size)
        : _size(size)
        , _pool(new char[static_cast<umsize_t>(_size)])
        , _allocated(0)
        , _times(0)
    { }

    ~Pool()
    {
        delete[] _pool;
    }

    template<typename T>
    void* allocate(msize_t cnt)
    {
        if (cnt != 1) {
            noop();
        }
        auto size = cnt * static_cast<msize_t>(sizeof(T));
        if (_allocated + size > _size) {
            throw std::bad_alloc();
        }
        auto result = _pool + _allocated;
        _allocated += size;
        ++_times;
        return result;
    }

    void deallocate(void* /*ptr*/)
    {
    }

    msize_t get_allocated() const
    {
        return _allocated;
    }

    msize_t get_times() const
    {
        return _times;
    }

private:
    Pool(const Pool&);
    Pool& operator=(const Pool&);

    msize_t const _size;
    char* const _pool;
    msize_t _allocated;
    msize_t _times;
};



///
///
///
template<typename T>
class CustomAllocator
{
public:
    typedef T value_type;
    typedef value_type* pointer;
    typedef const value_type* const_pointer;
    typedef value_type& reference;
    typedef const value_type& const_reference;

    template<typename U>
    struct rebind { typedef CustomAllocator<U> other; };

    CustomAllocator(Pool& pool)
        : _pool(pool)
    { }

    CustomAllocator(const CustomAllocator& other)
        : _pool(other._pool)
    { }

    template<typename U>
    CustomAllocator(const CustomAllocator<U>& other)
        : _pool(other._pool)
    { }

    value_type* allocate(size_t cnt)
    {
        //return static_cast<value_type*>(::operator new(cnt * sizeof(value_type)));

        return static_cast<value_type*>(_pool.allocate<value_type>(static_cast<msize_t>(cnt)));
    }

    void deallocate(value_type* ptr, size_t)
    {
        //::operator delete(ptr);

        _pool.deallocate(ptr);
    }

    void construct(value_type* ptr, const value_type& t) const { new(ptr) value_type(t); }
    void destroy(value_type* ptr) const { /* MSVC C4100 workaround */noop(ptr); ptr->~value_type(); }

    Pool& _pool;
};

template<typename T, typename U>
bool operator==(CustomAllocator<T> const&, CustomAllocator<U> const&)
{
    return true;
}

template<typename T, typename U>
bool operator!=(CustomAllocator<T> const& x, CustomAllocator<U> const& y)
{
    return !(x == y);
}

}   // namespace alloc



namespace math {

///
///
///
int inverse(int x, int mod)
{
    int t = 0; int newt = 1;
    int r = mod; int newr = x;
    while (newr != 0) {
        int quotient = r / newr;
        int tmp;

        tmp = t;
        t = newt;
        newt = tmp - quotient * newt;

        tmp = r;
        r = newr;
        newr = tmp - quotient * newr;
    }
    assert(r == 1);
    if (t < 0) {
        t += mod;
    }
    return t;
}

}   // namespace math



namespace hash {

///
///
///
struct RabinKarpHasher
{
    RabinKarpHasher(msize_t size_max)
        : Base_To_Size(nullptr)
        , Inverse_Base_To_Size(nullptr)
    {
        Base_To_Size = new int[static_cast<umsize_t>(size_max + 1)];
        Inverse_Base_To_Size = new int[static_cast<umsize_t>(size_max + 1)];

        long long value = 1;
        Base_To_Size[0] = static_cast<int>(value);
        Inverse_Base_To_Size[0] = pali::math::inverse(static_cast<int>(value), Mod);
        for (mindex_t i=1; i <= size_max; ++i) {
            value *= Base;
            value %= Mod;
            Base_To_Size[i] = static_cast<int>(value);
            Inverse_Base_To_Size[i] = pali::math::inverse(static_cast<int>(value), Mod);
        }
    }

    ~RabinKarpHasher()
    {
        delete[] Base_To_Size;
        delete[] Inverse_Base_To_Size;
    }

    int hash(const std::vector<int>& tab, mindex_t from, msize_t size)
    {
        long long result = 0;
        for (mindex_t i=from; i <= from + size - 1; ++i) {
            result *= Base;
            result %= Mod;
            result += hv(tab[static_cast<umindex_t>(i)]);
            result %= Mod;
        }
        return static_cast<int>(result);
    }

    int hash(const int* tab, mindex_t from, msize_t size)
    {
        long long result = 0;
        for (mindex_t i=from; i <= from + size - 1; ++i) {
            result *= Base;
            result %= Mod;
            result += hv(tab[i]);
            result %= Mod;
        }
        return static_cast<int>(result);
    }

    int hash_next(const std::vector<int>& tab, int prev, mindex_t to)
    {
        long long result = prev;
        result *= Base;
        result %= Mod;
        result += hv(tab[static_cast<umindex_t>(to)]);
        result %= Mod;
        return static_cast<int>(result);
    }

    int hash_next(const int* tab, int prev, mindex_t to)
    {
        long long result = prev;
        result *= Base;
        result %= Mod;
        result += hv(tab[to]);
        result %= Mod;
        return static_cast<int>(result);
    }

    int hash_roll(const std::vector<int>& tab, int prev, mindex_t to, msize_t size)
    {
        long long result = prev;
        result *= Base;
        result %= Mod;
        result += hv(tab[static_cast<umindex_t>(to)]);
        result %= Mod;
        long long val = Base_To_Size[size] * hv(tab[static_cast<umindex_t>(to - size)]);
        val %= Mod;
        result += Mod - val;
        result %= Mod;
        return static_cast<int>(result);
    }

    int hash_roll(const int* tab, int prev, mindex_t to, msize_t size)
    {
        long long result = prev;
        result *= Base;
        result %= Mod;
        result += hv(tab[to]);
        result %= Mod;
        long long val = Base_To_Size[size] * hv(tab[to - size]);
        val %= Mod;
        result += Mod - val;
        result %= Mod;
        return static_cast<int>(result);
    }

    int sub_hash(int a, int b, int pos_diff)
    {
        long long result = a;
        result += Mod;
        result -= b;
        result *= Inverse_Base_To_Size[pos_diff];
        result %= Mod;
        return static_cast<int>(result);
    }

private:
    RabinKarpHasher(const RabinKarpHasher&);
    RabinKarpHasher& operator=(const RabinKarpHasher&);

    static const int Base = 131071;
    static const int Mod = 524287;
    int* Base_To_Size;
    int* Inverse_Base_To_Size;

    int hv(int x)
    {
        return x;
    }
};

}   // namespace hash

}   // namespace pali

#endif   // PALI_HPP

/*}}}*/



const int N_max = 500;
const int A_max = 20'000;

bool has[N_max * A_max * 2 + 1];
bool only1[N_max * A_max * 2 + 1];
int times[N_max * A_max * 2 + 1];
#define times_key(x) ((x) + N_max * A_max)

typedef long long count_t;
#define cast_count_t(x) static_cast<count_t>(x)

int main()
{
    std::cin.tie(nullptr);
    std::ios::sync_with_stdio(false);

    unsigned int N; std::cin >> N;
    std::vector<int> ucb;
    ucb.reserve(N);
    std::vector<int> sumto; // 1-based
    sumto.reserve(N + 1);
    int sum = 0;
    sumto.push_back(0);
    for (unsigned int i = 0; i < N; ++i) {
        int a; std::cin >> a;
        ucb.push_back(a);
        sum += a;
        sumto.push_back(sum);
    }
    std::vector<int> buc;
    buc.reserve(N * N);
    int buc_min = N_max * A_max;
    int buc_max = -N_max * A_max;
    for (unsigned int i = 0; i < N; ++i) {
        for (unsigned int j = i; j < N; ++j) {
            int x = sumto[j + 1] - sumto[i - 1 + 1];
            int x_key = times_key(x);
            has[x_key] = true;
            ++times[x_key];
            if (times[x_key] == 1) {
                buc.push_back(x);
                only1[x_key] = true;
                if (buc_min > x) {
                    buc_min = x;
                }
                if (buc_max < x) {
                    buc_max = x;
                }
            } else {
                only1[x_key] = false;
            }
        }
    }
    count_t count = 0;
    std::sort(buc.begin(), buc.end());
    unsigned int buc_len = static_cast<unsigned int>(buc.size());
    for (unsigned int i = 0; i < buc_len - 1; ++i) {
        int a = buc[i];
        if (a > 0) {
            break;
        }
        bool check_abc = true;
        for (unsigned int j = i + 1; j < buc_len; ++j) {
            int b = buc[j];
            int c = -(a + b);
            if (c <= b) {
                check_abc = false;
            }
            if (c > buc_max) {
                continue;
            } else if (c < a) {
                break;
            } else if (c == a) { // 2 * a + b
                if (!only1[times_key(a)]) {
                    count += (cast_count_t(times[times_key(a)]) * (cast_count_t(times[times_key(a)]) - 1)) / 2 * cast_count_t(times[times_key(b)]);
                }
            } else if (c == b) { // a + 2 * b
                if (!only1[times_key(b)]) {
                    count += cast_count_t(times[times_key(a)]) * (cast_count_t(times[times_key(b)]) * (cast_count_t(times[times_key(b)]) - 1)) / 2;
                }
            } else if (check_abc && j < buc_len - 1) { // a + b + c
                int closest_c = buc[j + 1];
                if (c < closest_c) {
                    check_abc = false;
                } else if (has[times_key(c)]) {
                    count += cast_count_t(times[times_key(a)]) * cast_count_t(times[times_key(b)]) * cast_count_t(times[times_key(c)]);
                }
            }
        }
    }
    if (times[times_key(0)] >= 3) {
        count += (cast_count_t(times[times_key(0)]) * (cast_count_t(times[times_key(0)]) - 1) * (cast_count_t(times[times_key(0)]) - 2)) / 6;
    }
    std::cout << count;
}

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/*{{{ Includer.IncludeFiles(ctx, {[[C:\Projekty\r e p o\pali\src\main\pali.hpp]]}) ===*/
/*
  {   -- filePaths
    [[C:\Projekty\r e p o\pali\src\main\pali.hpp]],
  },
*/
#ifndef PALI_HPP
#define PALI_HPP

///
///
///
/*{{{ Includer.IncludeFiles(ctx, {[[C:\Projekty\r e p o\CommonLibrary_cpp\src\main\no_sillywarnings_please.h]]}) ===*/
/*
  {   -- filePaths
    [[C:\Projekty\r e p o\CommonLibrary_cpp\src\main\no_sillywarnings_please.h]],
  },
*/
// Based on no_sillywarnings_please, Copyright (c) Alf P. Steinbach, 2010.
// See https://alfps.wordpress.com/the-no_sillywarnings_please-h-file/ .
// Extra warnings added for /Wall.

#ifndef PROGROCK_CPPX_COMPILERSPECIFIC_MSVC_NOSILLYWARNINGSPLEASE_H
#define PROGROCK_CPPX_COMPILERSPECIFIC_MSVC_NOSILLYWARNINGSPLEASE_H

#ifdef _MSC_VER

// The following are real warnings but are generated by almost all MS headers, including
// standard library headers, so it's impractical to leave them on.
#pragma  warning( disable: 4619 )   // there is no warning number 'XXXX'
#pragma  warning( disable: 4668 )   // XXX is not defined as a preprocessor macro

// The following are pure sillywarnings:
#pragma warning( disable: 4061 )    // enum value is not *explicitly* handled in switch
#pragma warning( disable: 4099 )    // first seen using 'struct' now seen using 'class'
#pragma warning( disable: 4127 )    // conditional expression is constant
#pragma warning( disable: 4217 )    // member template isn't copy constructor
#pragma warning( disable: 4250 )    // inherits (implements) some member via dominance
#pragma warning( disable: 4251 )    // needs to have dll-interface to be used by clients
#pragma warning( disable: 4275 )    // exported class derived from non-exported class
#pragma warning( disable: 4347 )    // "behavior change", function called instead of template
#pragma warning( disable: 4355 )    // "'this': used in member initializer list
#pragma warning( disable: 4428 )    // MSVC 9: universal-character-name encountered in source
#pragma warning( disable: 4505 )    // unreferenced function has been removed
#pragma warning( disable: 4510 )    // default constructor could not be generated
#pragma warning( disable: 4511 )    // copy constructor could not be generated
#pragma warning( disable: 4512 )    // assignment operator could not be generated
#pragma warning( disable: 4513 )    // destructor could not be generated
#pragma warning( disable: 4610 )    // can never be instantiated user defined constructor required
#pragma warning( disable: 4623 )    // default constructor could not be generated
#pragma warning( disable: 4624 )    // destructor could not be generated
#pragma warning( disable: 4625 )    // copy constructor could not be generated
#pragma warning( disable: 4626 )    // assignment operator could not be generated
#pragma warning( disable: 4640 )    // a local static object is not thread-safe
#pragma warning( disable: 4661 )    // a member of the template class is not defined.
#pragma warning( disable: 4670 )    // a base class of an exception class is inaccessible for catch
#pragma warning( disable: 4672 )    // a base class of an exception class is ambiguous for catch
#pragma warning( disable: 4673 )    // a base class of an exception class is inaccessible for catch
#pragma warning( disable: 4675 )    // resolved overload was found by argument-dependent lookup
#pragma warning( disable: 4702 )    // unreachable code, e.g. in <list> header.
#pragma warning( disable: 4710 )    // call was not inlined
#pragma warning( disable: 4711 )    // call was inlined
#pragma warning( disable: 4820 )    // some padding was added
#pragma warning( disable: 4917 )    // a GUID can only be associated with a class, interface or namespace
#pragma warning( disable: 4996 )    // MSVC 9: a C std library function has been "deprecated" (says MS)

// Extra for /Wall:
#pragma warning( disable: 4350 )    // behavior change: 'member1' called instead of 'member2'
#pragma warning( disable: 4351 )    // new behavior: elements of array 'array' will be default initialized
#pragma warning( disable: 4464 )    // relative include path contains '..'
#pragma warning( disable: 4514 )    // 'function' : unreferenced inline function has been removed
#pragma warning( disable: 4718 )    // 'function call' : recursive call has no side effects, deleting
#pragma warning( disable: 5027 )    // 'type': move assignment operator was implicitly defined as deleted
#pragma warning( disable: 5045 )    // Compiler will insert Spectre mitigation for memory load if /Qspectre switch specified

#endif   // _MSC_VER

#endif   // PROGROCK_CPPX_COMPILERSPECIFIC_MSVC_NOSILLYWARNINGSPLEASE_H

/*}}}*/



///
///
///
/*{{{ Includer.IncludeFiles(ctx, {[[C:\Projekty\r e p o\CommonLibrary_cpp\src\main\disable_warnings.h]]}) ===*/
/*
  {   -- filePaths
    [[C:\Projekty\r e p o\CommonLibrary_cpp\src\main\disable_warnings.h]],
  },
*/
#ifdef _MSC_VER
#   pragma warning( push )
#   pragma warning( disable: 4100 )
#   pragma warning( disable: 4189 )     // 'identifier' : local variable is initialized but not referenced
#   pragma warning( disable: 4191 )
#   pragma warning( disable: 4242 )
#   pragma warning( disable: 4244 )
#   pragma warning( disable: 4267 )
#   pragma warning( disable: 4350 )
#   pragma warning( disable: 4365 )
#   pragma warning( disable: 4371 )
#   pragma warning( disable: 4548 )
#   pragma warning( disable: 4643 )
#   pragma warning( disable: 4647 )
#   pragma warning( disable: 4738 )
#   pragma warning( disable: 4774 )     // '<function>' : format string expected in argument <position> is not a string literal
#   pragma warning( disable: 4820 )
#   pragma warning( disable: 4987 )
#   pragma warning( disable: 5026 )
#   pragma warning( disable: 5027 )
#   pragma warning( disable: 5031 )     // #pragma warning(pop): likely mismatch, popping warning state pushed in different file
#   pragma warning( disable: 5219 )     // implicit conversion from 'type-1' to 'type-2', possible loss of data
#   pragma warning( disable: 5243 )     // 'type-name': using incomplete class 'class-name' can cause potential one definition rule violation due to ABI limitation
#endif

#ifdef __GNUC__
#   pragma GCC diagnostic push
#   pragma GCC diagnostic ignored "-Wpedantic"
#   pragma GCC diagnostic ignored "-Weffc++"
#   pragma GCC diagnostic ignored "-Wconversion"
#   pragma GCC diagnostic ignored "-Wsign-conversion"
#   pragma GCC diagnostic ignored "-Wshadow"
#   pragma GCC diagnostic ignored "-Wstrict-aliasing"
#endif

/*}}}*/

#ifdef UNDEF_NDEBUG
#undef NDEBUG
#endif

#include <cstddef>
#include <cassert>
#include <algorithm>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <memory>
#include <limits>
#include <iostream>

/*{{{ Includer.IncludeFiles(ctx, {[[C:\Projekty\r e p o\CommonLibrary_cpp\src\main\reenable_warnings.h]]}) ===*/
/*
  {   -- filePaths
    [[C:\Projekty\r e p o\CommonLibrary_cpp\src\main\reenable_warnings.h]],
  },
*/
#ifdef _MSC_VER
#   pragma warning( pop )
#endif

#ifdef __GNUC__
#   pragma GCC diagnostic pop
#endif

/*}}}*/



///
///
///
void noop(...) { }

///
///
///
#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))

///
///
///
#define NON_COPYABLE(C) \
    C(const C&) = delete; \
    C& operator=(const C&) = delete;

///
///
///
#define NON_MOVABLE(C) \
    C(C&&) = delete; \
    C& operator=(C&&) = delete;

///
///
///
#define NON_DESTRUCTIBLE(C) \
    ~C() = delete;

///
///
///
template<typename T>
void debug_echo(T x, const char* name, const char* delim, int line)
{
    std::cout
        << "DEBUG_ECHO   " << name << ": "
        << delim << x << delim
        << "   (line " << line << ")"
        << '\n';
}

///
///
///
#define DEBUG_ECHO(x) do { debug_echo(x, #x, "", __LINE__); } while (0)

///
///
///
#define DEBUG_ECHO_DELIM(x, delim) do { debug_echo(x, #x, delim, __LINE__); } while (0)



namespace pali {

///
///
///
typedef size_t umsize_t;
typedef ptrdiff_t msize_t;
typedef size_t umindex_t;
typedef ptrdiff_t mindex_t;
typedef ptrdiff_t munidiff_t;

const mindex_t Null_Index = -1;

const int Uninitialized_Positively = 7777777;
const int Uninitialized_Negatively = -Uninitialized_Positively;

}



///
///
///
#ifdef OVERRIDE_NEW_DELETE

namespace pali { namespace new_alloc {
    msize_t _allocated;
    msize_t _times;

    msize_t get_allocated()
    {
        return _allocated;
    }

    msize_t get_times()
    {
        return _times;
    }

    void clear_counters()
    {
        _allocated = 0;
        _times = 0;
    }
}}

void* operator new(size_t size)
{
    pali::new_alloc::_allocated += static_cast<pali::msize_t>(size);
    ++pali::new_alloc::_times;
    return malloc(size);
}

void* operator new[](size_t size)
{
    pali::new_alloc::_allocated += static_cast<pali::msize_t>(size);
    ++pali::new_alloc::_times;
    return malloc(size);
}

void operator delete(void* ptr) noexcept
{
    free(ptr);
}

void operator delete[](void* ptr) noexcept
{
    free(ptr);
}

#endif   // OVERRIDE_NEW_DELETE



namespace pali {

namespace alloc {

///
///
///
class Pool
{
public:
    Pool(msize_t size)
        : _size(size)
        , _pool(new char[static_cast<umsize_t>(_size)])
        , _allocated(0)
        , _times(0)
    { }

    ~Pool()
    {
        delete[] _pool;
    }

    template<typename T>
    void* allocate(msize_t cnt)
    {
        if (cnt != 1) {
            noop();
        }
        auto size = cnt * static_cast<msize_t>(sizeof(T));
        if (_allocated + size > _size) {
            throw std::bad_alloc();
        }
        auto result = _pool + _allocated;
        _allocated += size;
        ++_times;
        return result;
    }

    void deallocate(void* /*ptr*/)
    {
    }

    msize_t get_allocated() const
    {
        return _allocated;
    }

    msize_t get_times() const
    {
        return _times;
    }

private:
    Pool(const Pool&);
    Pool& operator=(const Pool&);

    msize_t const _size;
    char* const _pool;
    msize_t _allocated;
    msize_t _times;
};



///
///
///
template<typename T>
class CustomAllocator
{
public:
    typedef T value_type;
    typedef value_type* pointer;
    typedef const value_type* const_pointer;
    typedef value_type& reference;
    typedef const value_type& const_reference;

    template<typename U>
    struct rebind { typedef CustomAllocator<U> other; };

    CustomAllocator(Pool& pool)
        : _pool(pool)
    { }

    CustomAllocator(const CustomAllocator& other)
        : _pool(other._pool)
    { }

    template<typename U>
    CustomAllocator(const CustomAllocator<U>& other)
        : _pool(other._pool)
    { }

    value_type* allocate(size_t cnt)
    {
        //return static_cast<value_type*>(::operator new(cnt * sizeof(value_type)));

        return static_cast<value_type*>(_pool.allocate<value_type>(static_cast<msize_t>(cnt)));
    }

    void deallocate(value_type* ptr, size_t)
    {
        //::operator delete(ptr);

        _pool.deallocate(ptr);
    }

    void construct(value_type* ptr, const value_type& t) const { new(ptr) value_type(t); }
    void destroy(value_type* ptr) const { /* MSVC C4100 workaround */noop(ptr); ptr->~value_type(); }

    Pool& _pool;
};

template<typename T, typename U>
bool operator==(CustomAllocator<T> const&, CustomAllocator<U> const&)
{
    return true;
}

template<typename T, typename U>
bool operator!=(CustomAllocator<T> const& x, CustomAllocator<U> const& y)
{
    return !(x == y);
}

}   // namespace alloc



namespace math {

///
///
///
int inverse(int x, int mod)
{
    int t = 0; int newt = 1;
    int r = mod; int newr = x;
    while (newr != 0) {
        int quotient = r / newr;
        int tmp;

        tmp = t;
        t = newt;
        newt = tmp - quotient * newt;

        tmp = r;
        r = newr;
        newr = tmp - quotient * newr;
    }
    assert(r == 1);
    if (t < 0) {
        t += mod;
    }
    return t;
}

}   // namespace math



namespace hash {

///
///
///
struct RabinKarpHasher
{
    RabinKarpHasher(msize_t size_max)
        : Base_To_Size(nullptr)
        , Inverse_Base_To_Size(nullptr)
    {
        Base_To_Size = new int[static_cast<umsize_t>(size_max + 1)];
        Inverse_Base_To_Size = new int[static_cast<umsize_t>(size_max + 1)];

        long long value = 1;
        Base_To_Size[0] = static_cast<int>(value);
        Inverse_Base_To_Size[0] = pali::math::inverse(static_cast<int>(value), Mod);
        for (mindex_t i=1; i <= size_max; ++i) {
            value *= Base;
            value %= Mod;
            Base_To_Size[i] = static_cast<int>(value);
            Inverse_Base_To_Size[i] = pali::math::inverse(static_cast<int>(value), Mod);
        }
    }

    ~RabinKarpHasher()
    {
        delete[] Base_To_Size;
        delete[] Inverse_Base_To_Size;
    }

    int hash(const std::vector<int>& tab, mindex_t from, msize_t size)
    {
        long long result = 0;
        for (mindex_t i=from; i <= from + size - 1; ++i) {
            result *= Base;
            result %= Mod;
            result += hv(tab[static_cast<umindex_t>(i)]);
            result %= Mod;
        }
        return static_cast<int>(result);
    }

    int hash(const int* tab, mindex_t from, msize_t size)
    {
        long long result = 0;
        for (mindex_t i=from; i <= from + size - 1; ++i) {
            result *= Base;
            result %= Mod;
            result += hv(tab[i]);
            result %= Mod;
        }
        return static_cast<int>(result);
    }

    int hash_next(const std::vector<int>& tab, int prev, mindex_t to)
    {
        long long result = prev;
        result *= Base;
        result %= Mod;
        result += hv(tab[static_cast<umindex_t>(to)]);
        result %= Mod;
        return static_cast<int>(result);
    }

    int hash_next(const int* tab, int prev, mindex_t to)
    {
        long long result = prev;
        result *= Base;
        result %= Mod;
        result += hv(tab[to]);
        result %= Mod;
        return static_cast<int>(result);
    }

    int hash_roll(const std::vector<int>& tab, int prev, mindex_t to, msize_t size)
    {
        long long result = prev;
        result *= Base;
        result %= Mod;
        result += hv(tab[static_cast<umindex_t>(to)]);
        result %= Mod;
        long long val = Base_To_Size[size] * hv(tab[static_cast<umindex_t>(to - size)]);
        val %= Mod;
        result += Mod - val;
        result %= Mod;
        return static_cast<int>(result);
    }

    int hash_roll(const int* tab, int prev, mindex_t to, msize_t size)
    {
        long long result = prev;
        result *= Base;
        result %= Mod;
        result += hv(tab[to]);
        result %= Mod;
        long long val = Base_To_Size[size] * hv(tab[to - size]);
        val %= Mod;
        result += Mod - val;
        result %= Mod;
        return static_cast<int>(result);
    }

    int sub_hash(int a, int b, int pos_diff)
    {
        long long result = a;
        result += Mod;
        result -= b;
        result *= Inverse_Base_To_Size[pos_diff];
        result %= Mod;
        return static_cast<int>(result);
    }

private:
    RabinKarpHasher(const RabinKarpHasher&);
    RabinKarpHasher& operator=(const RabinKarpHasher&);

    static const int Base = 131071;
    static const int Mod = 524287;
    int* Base_To_Size;
    int* Inverse_Base_To_Size;

    int hv(int x)
    {
        return x;
    }
};

}   // namespace hash

}   // namespace pali

#endif   // PALI_HPP

/*}}}*/



const int N_max = 500;
const int A_max = 20'000;

bool has[N_max * A_max * 2 + 1];
bool only1[N_max * A_max * 2 + 1];
int times[N_max * A_max * 2 + 1];
#define times_key(x) ((x) + N_max * A_max)

typedef long long count_t;
#define cast_count_t(x) static_cast<count_t>(x)

int main()
{
    std::cin.tie(nullptr);
    std::ios::sync_with_stdio(false);

    unsigned int N; std::cin >> N;
    std::vector<int> ucb;
    ucb.reserve(N);
    std::vector<int> sumto; // 1-based
    sumto.reserve(N + 1);
    int sum = 0;
    sumto.push_back(0);
    for (unsigned int i = 0; i < N; ++i) {
        int a; std::cin >> a;
        ucb.push_back(a);
        sum += a;
        sumto.push_back(sum);
    }
    std::vector<int> buc;
    buc.reserve(N * N);
    int buc_min = N_max * A_max;
    int buc_max = -N_max * A_max;
    for (unsigned int i = 0; i < N; ++i) {
        for (unsigned int j = i; j < N; ++j) {
            int x = sumto[j + 1] - sumto[i - 1 + 1];
            int x_key = times_key(x);
            has[x_key] = true;
            ++times[x_key];
            if (times[x_key] == 1) {
                buc.push_back(x);
                only1[x_key] = true;
                if (buc_min > x) {
                    buc_min = x;
                }
                if (buc_max < x) {
                    buc_max = x;
                }
            } else {
                only1[x_key] = false;
            }
        }
    }
    count_t count = 0;
    std::sort(buc.begin(), buc.end());
    unsigned int buc_len = static_cast<unsigned int>(buc.size());
    for (unsigned int i = 0; i < buc_len - 1; ++i) {
        int a = buc[i];
        if (a > 0) {
            break;
        }
        bool check_abc = true;
        for (unsigned int j = i + 1; j < buc_len; ++j) {
            int b = buc[j];
            int c = -(a + b);
            if (c <= b) {
                check_abc = false;
            }
            if (c > buc_max) {
                continue;
            } else if (c < a) {
                break;
            } else if (c == a) { // 2 * a + b
                if (!only1[times_key(a)]) {
                    count += (cast_count_t(times[times_key(a)]) * (cast_count_t(times[times_key(a)]) - 1)) / 2 * cast_count_t(times[times_key(b)]);
                }
            } else if (c == b) { // a + 2 * b
                if (!only1[times_key(b)]) {
                    count += cast_count_t(times[times_key(a)]) * (cast_count_t(times[times_key(b)]) * (cast_count_t(times[times_key(b)]) - 1)) / 2;
                }
            } else if (check_abc && j < buc_len - 1) { // a + b + c
                int closest_c = buc[j + 1];
                if (c < closest_c) {
                    check_abc = false;
                } else if (has[times_key(c)]) {
                    count += cast_count_t(times[times_key(a)]) * cast_count_t(times[times_key(b)]) * cast_count_t(times[times_key(c)]);
                }
            }
        }
    }
    if (times[times_key(0)] >= 3) {
        count += (cast_count_t(times[times_key(0)]) * (cast_count_t(times[times_key(0)]) - 1) * (cast_count_t(times[times_key(0)]) - 2)) / 6;
    }
    std::cout << count;
}