#include<bits/stdc++.h>
using namespace std;
int goodcount(vector<int>&v){
    unordered_map<int,int>m;
    int sum=0,count=0;m[1]=1;
    for(int i=0;i<v.size();i++){
        sum+=v[i];
        if(m.find(sum-i)!=m.end()){
            count+=m[sum-i];
        }
        m[sum-i]++;
    }
    return count;
}
int main(){
    int n;cin>>n;
    vector<int>v(n);
    for(int i=0;i<n;i++)cin>>v[i];
    cout<<goodcount(v)<<endl;
}