题解

线段树(Segment Tree) 树状数组(Fenwick Tree)

#include<stdio.h>

int one,another,array[100010],prefixSum[100010];
int main() {
    scanf("%d%d",&one,&another);
    for (int index=1;index<=one;index++) scanf("%d",&array[index]);
    prefixSum[1]=array[1];
    for (int index=2;index<=one;index++) prefixSum[index]=prefixSum[index-1]+array[index];
    while(another--){
        int left,right;
        scanf("%d%d",&left,&right);
        printf("%d",prefixSum[right]-prefixSum[left-1])
    }
}