线段树——线段树1（求和）

线段树——线段树1（求和）

#include<bits/stdc++.h>
using namespace std;
#define IOS ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define int long long
#define endl '\n'
const int N=1e5+114;
int n,m;
int s[N];
struct node{
	int l,r,val,lazy;
}tree[2*N];
void build(int l,int r,int num){
	tree[num].l=l;tree[num].r=r;
	if(l==r){
		tree[num].val=s[l];
		return;
	}
	int mid=l+(r-l)/2;
	build(l,mid,2*num);
	build(mid+1,r,2*num+1);
	tree[num].val=tree[2*num].val+tree[2*num+1].val;
	return;
}
int getsum(int tarl,int tarr,int num){
	if(tree[num].l>=tarl&&tree[num].r<=tarr)
		return tree[num].val+tree[num].lazy*(tree[num].r-tree[num].l+1);
	if(tree[num].r<tarl||tree[num].l>tarr)return 0;
	if(tree[num].lazy){
		tree[num].val+=tree[num].lazy*(tree[num].r-tree[num].l+1);
		tree[2*num].lazy+=tree[num].lazy;
		tree[2*num+1].lazy+=tree[num].lazy;
		tree[num].lazy=0;
	}
	int ans=0;
	ans+=getsum(tarl,tarr,2*num);
	ans+=getsum(tarl,tarr,2*num+1);
	return ans;
}
void add(int tarl,int tarr,int num,int plus){
	if(tree[num].l>=tarl&&tree[num].r<=tarr){
		tree[num].lazy+=plus;
		return;
	}
	if(tree[num].r<tarl||tree[num].l>tarr)return;
	if(tree[num].lazy!=0){
		tree[2*num].lazy+=tree[num].lazy;
		tree[2*num+1].lazy+=tree[num].lazy;
		tree[num].val+=tree[num].lazy*(tree[num].r-tree[num].l+1);
		tree[num].lazy=0;
	}
	tree[num].val+=plus*(min(tree[num].r,tarr)-max(tree[num].l,tarl)+1);
	add(tarl,tarr,2*num,plus);
	add(tarl,tarr,2*num+1,plus);
	return;
}
signed main(){
	IOS
	cin>>n>>m;
	for(int i=1;i<=n;i++)cin>>s[i];
	build(1,n,1);
	while(m--){
		int which;
		cin>>which;
		if(which==1){
			int l,r,plus;
			cin>>l>>r>>plus;
			add(l,r,1,plus);
		}
		else {
			int l,r;
			cin>>l>>r;
			cout<<getsum(l,r,1)<<endl;
		}
	}
	return 0;
}