[树状数组] 区间查询区间求和 洛谷P3372

题目

题目链接：https://www.luogu.com.cn/problem/P3372

代码

#include<cstdio>
#include<cstring>
#include<cmath>
#include<cstdlib>
#include<cctype>
#include<ctime>
#include<iostream>
#include<string>
#include<map>
#include<queue>
#include<stack>
#include<set>
#include<vector>
#include<iomanip>
#include<list>
#include<bitset>
#include<sstream>
#include<fstream>
#include<complex>
#include<algorithm>
#if __cplusplus >= 201103L
#include <unordered_map>
#include <unordered_set>
#endif
#define ll long long
#define lowbit(x) (-x)&x
#define int long long
using namespace std;
const int INF = 0x3f3f3f3f;
int n,m;
int bit[500010],bit2[500010];
void edit(int pos,int val){
	for(int i=pos;i<=n;i+=lowbit(i)){
		bit[i]+=val;
		bit2[i]+=val*pos;
	}
}
void  range_edit(int l,int r,int val){
	edit(l,val);
	edit(r+1,-val);
}
int query(int x){
	int res=0;
	for(int i=x;i>0;i-=lowbit(i)){
		res+=bit[i]*(x+1)-bit2[i];
	}
	return res;
}

signed main(){
	ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
	cin>>n>>m;
	for(int i=1;i<=n;i++){
		int t;
		cin>>t;
		edit(i,t);
		edit(i+1,-t);
	}
	int st;
	for(int i=1;i<=m;i++){
		cin>>st;
		if(st==1){
			int a,b,c;
			cin>>a>>b>>c;
			range_edit(a,b,c);
		}
		else {
			int a,b;
			cin>>a>>b;
			cout<<query(b)-query(a-1)<<endl;
		}
	}
    return 0;
}

来源：CSDN

作者：kosf_

链接：https://blog.csdn.net/kosf_/article/details/104320091