蒟蒻求助 60分 #7~10 WA

#include<iostream>
#include<cstdio>
#include<string>
#include<algorithm>
#include<cmath>
#include<queue>
#include<vector>
#include<set>
#include<cstdio>
#include<ctime>
#include<stack>
#define int long long
#define lp (p<<1)
#define rp (p<<1|1)
#define mid ((l+r)>>1)
#define N 1000005
#define M N<<2
using namespace std;
int n,m,x,y,op,bj[M];
int a[N],maxx[M],add[M],vis[M];
int re()
{
    int x=0,p=1;
    char y=getchar();
    for(;y>'9'||y<'0';y=getchar())
        if(y=='-')
            p=-p;
    for(;y>='0'&&y<='9';y=getchar())
        x=x*10+y-'0';
    return x*p;
}
void wr(int x)
{
    if(x<0)
        x=-x,putchar('-');
    if(x>9)
        wr(x/10);
    putchar(x%10+'0');
}
void Push_up(int p){
    maxx[p]=max(maxx[lp],maxx[rp]);
}
void Push_down(int l,int r,int p){
    if(bj[p]){
        maxx[rp]=vis[p];
        maxx[lp]=vis[p];
        vis[lp]=vis[p];
        vis[rp]=vis[p];
        vis[p]=0;
        bj[p]=0;
        bj[rp]=1;
        bj[lp]=1;
    }
    if(add[p]){
        maxx[lp]+=add[p];
        maxx[rp]+=add[p];
        add[lp]+=add[p];
        add[rp]+=add[p];
        add[p]=0;
    }
}
void Build(int l,int r,int p){
    if(l==r){
        maxx[p]=a[l];
        return;
    }
    Build(l,mid,lp);
    Build(mid+1,r,rp);
    Push_up(p);
}
void Add(int al,int ar,int l,int r,int p,int k){
    if(al<=l&&ar>=r){
        maxx[p]+=k;
        add[p]+=k;
        return;
    }
    if(bj[p]||add[p])
        Push_down(l,r,p);
    if(al<=mid)
        Add(al,ar,l,mid,lp,k);
    if(ar>mid)
        Add(al,ar,mid+1,r,rp,k);
    Push_up(p);
}
void Change(int cl,int cr,int l,int r,int p,int k){
    if(cl<=l&&cr>=r){
        maxx[p]=k;
        bj[p]=1;
        vis[p]=k;
        add[p]=0;
        return;
    }
    if(bj[p]||add[p])
        Push_down(l,r,p);
    if(cl<=mid)
        Change(cl,cr,l,mid,lp,k);
    if(cr>mid)
        Change(cl,cr,mid+1,r,rp,k);
    Push_up(p);
}
int Max(int ml,int mr,int l,int r,int p){
    if(ml<=l&&mr>=r)
        return maxx[p];
    if(bj[p]||add[p])
        Push_down(l,r,p);
    int ans=-1e18;
    if(ml<=mid)
        ans=max(ans,Max(ml,mr,l,mid,lp));
    if(mr>mid)
        ans=max(ans,Max(ml,mr,mid+1,r,rp));
    return ans;
}
signed main()
{
    n=re(),m=re();
    for(int i=1;i<=n;i++)
        a[i]=re();
    Build(1,n,1);
    while(m--){
        op=re(),x=re(),y=re();
        if(op==1){
            int k=re();
            Change(x,y,1,n,1,k);
        }
        else if(op==2){
            int k=re();
            Add(x,y,1,n,1,k);
        }
        else if(op==3){
            wr(Max(x,y,1,n,1));putchar('\n');
        }
    }
    return 0;
}