7-9WA 10RE 萌新求调

#include<cstdio>
#include<cstdlib>
#include<iostream>
#define ll long long
using namespace std;
const int maxn=1000010;
int lson(int now){return now<<1;}
int rson(int now){return now<<1|1;}
struct node{
	ll val,lazyall,maxval,lazyadd;
	bool lazy;
}tree[maxn*4];
ll num[maxn];
void pushup(int now)
{
	tree[now].maxval=max(tree[lson(now)].maxval,tree[rson(now)].maxval);
}
void build(int now,int l,int r)
{
	tree[now].maxval=-9223372036854775807;
	if(l==r)
	{
		tree[now].maxval=num[l];
		tree[now].val=num[l];
		return;
	}
	int mid=(l+r)>>1;
	build(lson(now),l,mid);
	build(rson(now),mid+1,r);
	pushup(now);
}
void cover(int now,int l,int r)
{
	if(tree[now].lazy==1)
	{
	tree[lson(now)].maxval=tree[now].lazyall;
	tree[rson(now)].maxval=tree[now].lazyall;
	tree[lson(now)].lazyall=tree[now].lazyall;
	tree[rson(now)].lazyall=tree[now].lazyall;
	tree[now].lazyadd=0;
	tree[lson(now)].lazyadd=0;
	tree[rson(now)].lazyadd=0;
	}
}
void pushdown(int now,int l,int r)
{
	int mid=(l+r)>>1;
	cover(now,l,r);
	tree[lson(now)].maxval+=tree[now].lazyadd;
	tree[rson(now)].maxval+=tree[now].lazyadd;
	tree[lson(now)].lazyadd+=tree[now].lazyadd;
	tree[rson(now)].lazyadd+=tree[now].lazyadd;
	tree[now].lazyadd=0;
	tree[now].lazyall=0;
	tree[now].lazy=0;
}
void updatej(int now,int l,int r,int xgl,int xgr,ll k )
{
	if(xgr<l||r<xgl) return;
	if(xgl<=l&&r<=xgr)
	{
		cover(now,l,r);
		tree[now].maxval+=k;
		tree[now].lazyadd+=k;
		return;
	}
	int mid=(l+r)>>1;
	pushdown(now,l,r);
	updatej(lson(now),l,mid,xgl,xgr,k);
	updatej(rson(now),mid+1,r,xgl,xgr,k);
	pushup(now);
}
void updateb(int now,int l,int r,int xgl,int xgr,ll k )
{
	if(xgr<l||r<xgl) return;
	if(xgl<=l&&r<=xgr)
	{
		tree[now].lazyadd=0;
		tree[now].lazy=1;
		tree[now].maxval=k;
		tree[now].lazyall=k;
		return;
	}
	int mid=(l+r)>>1;
	pushdown(now,l,r);
	updateb(lson(now),l,mid,xgl,xgr,k);
	updateb(rson(now),mid+1,r,xgl,xgr,k);
	pushup(now);
}
ll query(int now,int l,int r,int xgl,int xgr)
{
	if(xgr<l||r<xgl) return -9223372036854775807;
	if(xgl<=l&&r<=xgr) return tree[now].maxval;
	int mid=(l+r)>>1;
	pushdown(now,l,r);
	return max(query(lson(now),l,mid,xgl,xgr),query(rson(now),mid+1,r,xgl,xgr));
}
int main(){
	int op;
	ll n,m,t1,t2,t3,t4;
	scanf("%lld%lld",&n,&m);
	for(int i=1;i<=n;i++)
	{
		scanf("%lld",&num[i]);
	}
	build(1,1,n);
	while(m--)
	{
		scanf("%d",&op);
		if(op==1)
		{
				scanf("%lld%lld%lld",&t2,&t3,&t4);
			updateb(1,1,n,t2,t3,t4);
		}
		else if(op==2)
		{
			scanf("%lld%lld%lld",&t2,&t3,&t4);
			updatej(1,1,n,t2,t3,t4);
		}
		else{
			scanf("%lld%lld",&t2,&t3);
			printf("%lld\n",query(1,1,n,t2,t3));
		}
	}
	return 0;
}