Luogu P8218 求区间和-JZTXT

题目描述

思路

直接套前缀和板子水题

Code

#include <iostream>
#include <cstdio>
#include <algorithm>

using namespace std;

int n, a[100005], b[100005], m, l[100005], r[100005];

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