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// Karol Kosinski 2024
#include <bits/stdc++.h>
#define FOR(i,a,b) for(int i=(a),_b=(b);i<_b;++i)
#define FR_(i,a,b) for(int i=(a),_b=(b);i<=_b;++i)
#define FD_(i,b,a) for(int i=(b),_a=(a);i>=_a;--i)
#define ALL(c) (c).begin(),(c).end()
#define SIZE(c) int((c).size())
#define X first
#define Y second
#define endl '\n'
#define NAM(x) #x,'=',x
using namespace std;
using LL = long long;
using ULL = unsigned long long;
using PII = pair<int, int>;
using TIII = tuple<int, int, int>;
template<class...T> void _cout(T...a){(cout<<...<<a);}

#ifndef ENABLE_DEBUG
#define DEB(k,p,f,x...)
#else
#define DEB(k,p,f,x...) {if(k)_cout("------",setw(4),__LINE__," : ",__FUNCTION__,endl);if(p)f(x);}
#endif
#define DEBF(f,x...)    DEB(1,1,f,x)
#define DEBL            DEBF(void,0)
#define DEBC(p,x...)    DEB(0,p,_cout,x)
#define DEBUG(x...)     DEBC(1,x)

constexpr int NX = 505;
constexpr int VX = 40'000'005;
constexpr int IV(int k) { return k * ( k + 1 ) / 2; }

LL A[NX], B[ IV(NX) ], TSums[VX];
LL* Sums = TSums + ( VX / 2 );

LL testcase()
{
    int n, k = 0;
    cin >> n;
    FOR(i,0,n) cin >> A[i];
    FOR(i,0,n)
    {
        B[ k ++ ] = A[i];
        DEBUG( B[ k - 1 ], ' ' );
        FOR(j,i+1,n)
        {
            B[k] = B[ k - 1 ] + A[j], ++ k;
            DEBUG( B[ k - 1 ], ' ' );
        }
        DEBUG(endl);
    }
    LL res = 0;
    ++ Sums[ B[1] + B[0] ];
    FOR(i,2,k-1)
    {
        res += Sums[ -B[i] ];
        FOR(j,0,i)
        {
            ++ Sums[ B[i] + B[j] ];
        }
    }
    res += Sums[ -B[ k - 1 ] ];
    return res;
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout << testcase() << endl;
    return 0;
}