P3372 模板线段树 1区间加 / 区间和

Posted 2021-11-23 辉小歌

https://www.luogu.com.cn/problem/P3372

#include<bits/stdc++.h>
using namespace std;
const int N=1e5+10;
typedef long long int LL;
int n,m;
int w[N];
struct node
{
	int l,r;
	LL sum,add;
}tr[N*4];
void pushup(int u)
{
	tr[u].sum=tr[u<<1].sum+tr[u<<1 | 1].sum;
}
void pushdown(int u)
{
	auto &root=tr[u],&left=tr[u<<1],&right=tr[u<<1 | 1];
	if(root.add)
	{
		left.add+=root.add,left.sum+=(LL)(left.r-left.l+1)*root.add;
		right.add+=root.add,right.sum+=(LL)(right.r-right.l+1)*root.add;
		root.add=0;
	}
}
void build(int u,int l,int r)
{
	if(l==r) tr[u]={l,r,w[r],0};
	else
	{
		tr[u]={l,r};
		int mid=l+r>>1;
		build(u<<1,l,mid),build(u<<1 | 1,mid+1,r);
		pushup(u);
	}
}
void modify(int u,int l,int r,int d)
{
	if(tr[u].l>=l&&tr[u].r<=r)
	{
		tr[u].sum+=(LL)(tr[u].r-tr[u].l+1)*d;
		tr[u].add+=d;
	}
	else//一定分裂 
	{
		pushdown(u);
		int mid=tr[u].l+tr[u].r>>1;
		if(l<=mid) modify(u<<1,l,r,d);
		if(r>mid) modify(u<<1 | 1,l,r,d);
		pushup(u);
	}
}
LL query(int u,int l,int r)
{
	if(tr[u].l>=l&&tr[u].r<=r) return tr[u].sum;
	pushdown(u);
	int mid=tr[u].l+tr[u].r>>1;
	LL sum=0;
	if(l<=mid) sum=query(u<<1,l,r);
	if(r>mid) sum+=query(u<<1 | 1,l,r);
	return sum;
}
int main(void)
{
    cin>>n>>m;
    for(int i=1;i<=n;i++) cin>>w[i];
    build(1,1,n);
    while(m--)
    {
        int op; cin>>op;
        if(op==2)
        {
            int l,r; cin>>l>>r;
            cout<<query(1,l,r)<<endl;
        }else
        {
            int l,r,d; cin>>l>>r>>d;
            modify(1,l,r,d);
        }
    }
	return 0;
}