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#include <vector>
#include <iostream>
#include <sstream>
#include <math.h>
#include <sys/time.h>
#include <cstdlib>
#include <algorithm>
#include <cassert>
#include <cstring>
#include <fstream>
#include <set>
#include <map>
#include <iomanip>
#include <queue>

#define FOR(i,a,b)  for(__typeof(b) i=(a);i<(b);++i)
#define REP(i,a)    FOR(i,0,a)
#define FOREACH(x,c)   for(__typeof(c.begin()) x=c.begin();x != c.end(); x++)
#define ALL(c)      c.begin(),c.end()
#define CLEAR(c)    memset(c,0,sizeof(c))
#define SIZE(c) (int) ((c).size())

#define PB          push_back
#define MP          make_pair
#define X           first
#define Y           second

#define ULL         unsigned long long
#define LL          long long
#define LD          long double
#define II         pair<int, int>
#define DD         pair<double, double>
#define FF          pair<float,float>

#define VC	    vector
#define VI          VC<int>
#define VVI         VC<VI>
#define VVVI        VC<VVI>
#define VD          VC<double>
#define VS          VC<string>
#define VII         VC<II>
#define VDD         VC<DD>
#define VFF         VC<FF>
#define VVD         VC<VD>
#define VVVD        VC<VVD>
#define VULL         VC<ULL>

#define DB(a)       cerr << #a << ": " << a << endl;

using namespace std;

template<class T> void print(VC < T > v) {cerr << "[";if (SIZE(v) != 0) cerr << v[0]; FOR(i, 1, SIZE(v)) cerr << "," << v[i]; cerr << "]\n";}
template<class T> string i2s(T &x) { ostringstream o; o << x; return o.str(); }
VS split(string &s, char c = ' ') {VS all; int p = 0, np; while (np = s.find(c, p), np >= 0) {all.PB(s.substr(p, np - p)); p = np + 1;} if (p < SIZE(s)) all.PB(s.substr(p)); return all;}

VI uc;
VI pref;

int main(int argc, char *argv[]){
    int N;
    cin >> N;
    uc.resize(N);
    REP(i,N)
        cin >> uc[i];
    pref.resize(N+1);
    pref[0] = 0;
    FOR(i,1,N+1)
        pref[i] = pref[i-1] + uc[i-1];

    map<int,ULL> S;
    REP(i1,N) FOR(i2,i1,N)
        S[ pref[i2+1]-pref[i1] ] += 1;

    ULL cnt=0;
    ULL neg=0;
    REP(i1,N) FOR(i2,i1,N) REP(j1,N) FOR(j2,j1,N)
    if (i1 < j1 || (i1 == j1 && i2 < j2) ){
        int s = pref[i2+1]-pref[i1] + pref[j2+1]-pref[j1];
        if (S.count(-s) > 0)
            cnt += S[-s];
        
        if ( 2*(pref[i2+1]-pref[i1]) + pref[j2+1]-pref[j1] == 0)
            neg++;

        if ( pref[i2+1]-pref[i1] + 2*(pref[j2+1]-pref[j1]) == 0)
            neg++;
    }


    cout << (cnt - neg)/3 << endl;
}