P3374 模板树状数组 1

Posted 2020-12-13 lightyachoo

P3374 【模板】树状数组 1

#include<bits/stdc++.h>
using namespace std;
const int N=5e5+10;
int n,m;
int a[N];
int c[N<<2];

int lowbit(int x){
	return x&-x;
}

void updata(int x,int k){
	while(x<=n){
		c[x]+=k;
		x+=lowbit(x);
	}
}

int getsum(int x){
	int ans=0;
	while(x){
		ans+=c[x];
		x-=lowbit(x);
	}
	return ans;
}

int main(){
	scanf("%d%d",&n,&m);
	for(int i=1;i<=n;i++){
		scanf("%d",&a[i]);
		updata(i,a[i]);
	}
	for(int i=1;i<=m;i++){
		int go;
		scanf("%d",&go);
		if(go==1){
			int x,y;
			scanf("%d%d",&x,&y);
			updata(x,y);
		}
		if(go==2){
			int x,y;
			scanf("%d%d",&x,&y);
			printf("%d
",getsum(y)-getsum(x-1));
		}
	}
	return 0;
}