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All submissions for this problem are available.

Read problems statements in Mandarin Chinese and Russian.

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 S_i, S_i+1, ..., S_j 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

存在任意两个数 gcd = 1 必然为n , 否则为 -1

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cstring>
#include <vector>
#include <queue>

using namespace std;
const int N = 100010;
int n , m , e[N] , ans ;
inline int gcd( int a , int b ) { return b == 0 ? a : gcd(b,a%b); }
int Run() {
    scanf("%d",&n);
    for( int i = 0 ; i < n ; ++i ) scanf("%d",&e[i]);
    sort( e , e + n );
    for( int i = 1 ; i < n ; ++i ) if( gcd(e[0],e[i]) == 1 ) {
        return n;
    }
    return -1;
}
int main()
{
    #ifdef LOCAL
        freopen("in","r",stdin);
    #endif
    ios::sync_with_stdio(0);
    int _ , cas = 1 ;
    scanf("%d",&_);
    while(_--) printf("%d\n",Run());
}

View Code

CodeChef CSUB Count Substrings

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原文地址：http://www.cnblogs.com/hlmark/p/4296777.html