学步园

Problem Description

Given a string S consisting of only 1s and 0s, find the number of substrings which start and end both in 1.
In this problem, a substring is defined as a sequence of continuous characters Si, Si+1, ..., Sj where 1 ≤ i ≤ j ≤ N.

Input

First line contains T, the number of testcases. Each testcase consists of N(the length of string) in one line and string in second line.

Output

For each testcase, print the required answer in one line.

Constraints

1 ≤ T ≤ 105
1 ≤ N ≤ 105
Sum of N over all testcases ≤ 105

Example

Input:

2
4
1111
5
10001

Output:

10
3

Explanation

test1: All substrings satisfy.
test2: Three substrings S[1,1], S[5,5] and S[1,5] satisfy.

题解

#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<iostream>
#include<cmath>
#include<algorithm>
#define ll long long
using namespace std;
int T,n;
ll ct;
char ch[100005];
int main()
{
	scanf("%d",&T);
	while(T--)
	   {scanf("%d",&n);
	    scanf("%s",ch);
	    int i;
	    ct=0;
	    for(i=0;i<n;i++)
		   {if(ch[i]=='1') ct++;}
		printf("%lld\n",(ct+1)*ct/2);
	   }
	return 0;
}