#include <iostream>
#include <cstring>

using namespace std;

const int N = 2e5+10;

typedef long long LL;

LL s[N];
int n;

bool check(int st,int mid)
{
    LL m=s[mid]-s[st];
    if(m>s[st]&&m>(s[n]-s[mid])) return true;
    return false;
}

int main()
{
    cin>>n;
    for(int i=1;i<=n;i++)
    {
        cin>>s[i];
        s[i]+=s[i-1];
    }
    LL ans=0;
    for(int i=1;i<=n;i++)
    {
        int l=i+1,r=n;
        while(l<r)
        {
            int mid=l+r>>1;
            if(check(i,mid)) r=mid;
            else l=mid+1;
        }
        if(l<n)
            ans+=n-l;
    }
    cout<<ans;
    return 0;
}