题目链接:http://acm.nyist.net/JudgeOnline/problem.php?pid=108
题目分析:
数组中存放数组的累加和,需要求b到e的和时,用到e的累加和减去到b-1的累加和即可。
#include<stdio.h> int arr[1000000]; int main() { int i; int n,m; int b,e; arr[0] = 0; while(scanf("%d %d", &n, &m) != EOF) { for(i = 1; i <= n; ++i) scanf("%d", &arr[i]); for(i = 1; i <= n; ++i) arr[i] += arr[i - 1]; for(i = 0; i < m; ++i) { scanf("%d %d", &b, &e); printf("%d\n", arr[e] - arr[b - 1]); } } return 0; }