Codeforces Beta Round #18 (Div2) C. Stripe 前缀和

思路：维护一个前缀和就可以了，水题

#include<bits/stdc++.h>
using namespace std;
const int maxn = 1e6;
int a[maxn],sum[maxn];
int main()
{
	int n;
    scanf("%d",&n);
	for(int i = 1;i<=n;i++)
		scanf("%d",&a[i]),sum[i]=a[i]+sum[i-1];
	int ans = 0;
	for(int i = 1;i<=n-1;i++)
		if(sum[i]==sum[n]-sum[i])
			ans++;
	printf("%d\n",ans);
}

Description

Once Bob took a paper stripe of n

Input

The first input line contains integer n (1 ≤ n ≤ 10⁵) — amount of squares in the stripe. The second line contains n

Output

Output the amount of ways to cut the stripe into two non-empty pieces so that the sum of numbers from one piece is equal to the sum of numbers from the other piece. Don't forget that it's allowed to cut the stripe along the squares' borders only.

Sample Input

Input

9 1 5 -6 7 9 -16 0 -2 2

Output

3

Input

3 1 1 1

Output

0

Input

2 0 0

Output

1