NYOJ 108 士兵杀敌(一)

#include <cstdio>
#include <iostream>
#include <cstring>
#define maxn 1000005
using namespace std;
int a[maxn];

int main()
{
	int n,m;
	scanf("%d%d",&n,&m);
	a[0] = 0;
	for(int i=1;i<=n;i++){
		scanf("%d",&a[i]);
		a[i] = a[i-1] + a[i];
	}
	while(m--){
		int c,b;
		scanf("%d%d",&c,&b);
		printf("%d\n",a[b]-a[c-1]);
	}
	return 0;
}