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#include<cstdio>
#include<algorithm>
#include<map>
#include<unordered_map>
#define S 507
#define S2 10'000'000
using namespace std;
typedef long long ll;

int pref[S];

// unordered_map<int,int> M;
// unordered_map<int,int> M2;

int inf = 3 * S2 + S2/2;

int M[7*S2];
int M2[7*S2];

int main(void){
    int n;
    scanf("%d", &n);
    for(int i = 1; i <= n; i++){
        int x;
        scanf("%d", &x);
        pref[i] = pref[i-1] + x;
    }

    ll ans = 0;
    ll twoSame1 = 0;
    ll threeSame = 0;
    
    for(int i = 0; i <= n; i++){
        for(int j = i+1; j <= n; j++){
            int p = pref[j] - pref[i];
            if(p == 0){
                threeSame++;
            }
            M2[p + inf]++;
        }
    }

    for(int i = 0; i <= n; i++){
        for(int j = i+1; j <= n; j++){
            int p = pref[j] - pref[i];
            p *= 2;
            if(p == 0){
                twoSame1 += M2[-p + inf] - 1;
            }else{
                twoSame1 += M2[-p + inf];
            }
            
        }
    }

    for(int j = 0; j <= n; j++){
        for(int k = j+1; k <= n; k++){
            int p = pref[k] - pref[j];
            M[p + inf]++;
        }
    }

    for(int i = 1; i <= n; i++){
        for(int j = 0; j <= n; j++){
            for(int k = j+1; k <= n; k++){
                int p = pref[k] - pref[j] + pref[i];
                ans += M[-p + inf];
            }
        }
        //teraz dodajemy
        for(int j = 0; j <= n; j++){
            for(int k = j+1; k <= n; k++){
                int p = pref[k] - pref[j] - pref[i];
                M[p + inf]++;
            }
        }
    }
    // twoSame2 += twoSame3;
    // twoSame1 -= twoSame2;

    twoSame1 *= 3;
    ans -= twoSame1;
    ans -= threeSame;
    ans /= 6;
    printf("%lld\n",ans);

    // printf("%lld %lld %lld %lld %lld*\n",ans,twoSame1, twoSame2, twoSame3, threeSame);
    
    // printf("%lld\n",ans);

    return 0;
}