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#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<int, int> pii;

const int N = 501;
const int X = 6e7+100;
const int B = 3e7+2;

int a[N], p[N], cnt[X], n;

void solve() {
    cin>>n;

    p[0]=0;
    for (int i=1; i<=n; ++i) cin>>a[i], p[i]=p[i-1]+a[i];

    ll res=0;
    for (int j=0; j<=n; ++j) {
        for (int i=1; i<=n; ++i) {
            for (int ip=0; ip<i; ++ip) {
                res+=cnt[p[i]-p[ip]+p[j]+B];
            }
        }

        for (int i=1; i<=n; ++i) {
            for (int ip=0; ip<i; ++ip) {
                ++cnt[p[ip]-p[i]+p[j]+B];
            }
        }
    } memset(cnt, 0, sizeof(cnt));
    
    for (int i=1; i<=n; ++i) {
        for (int ip=0; ip<i; ++ip) {
            ++cnt[2*(p[i]-p[ip])+B];
        }
    }

    for (int i=1; i<=n; ++i) {
        for (int ip=0; ip<i; ++ip) {
            res-=3*cnt[-(p[i]-p[ip])+B];
        }
    } 

    for (int i=1; i<=n; ++i) {
        for (int ip=0; ip<i; ++ip) {
            if (p[i]-p[ip] == 0) res+=2;
        }
    } assert(res%6 == 0);
    cout<<(res/6)<<"\n";
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);

    int t=1; //cin>>t;
    while (t--) solve();
}