tijie

随机化这一块

#include <bits/stdc++.h>
using namespace std;
const int maxn=5e5+5;
int q,n,m,cnt,sum,need;
long long w[maxn],ru[maxn],mx[maxn];
int main(){
    cin>>n>>m;
    mt19937 rnd(time(0));
    for(int i=1;i<=n;i++){
        w[i]=rnd();
        sum+=w[i];
    }
    for(int i=1;i<=m;i++){
        int u,v;
        cin>>u>>v;
        mx[v]+=w[u];
        ru[v]+=w[u];
        need+=w[u];
    }
    cin>>q;
    while(q--){
        int op,u,v;
        cin>>op;
        if(op==1){
            cin>>u>>v;
            need-=w[u];
            ru[v]-=w[u];
        }
        else if(op==2){
            cin>>u;
            need-=ru[u];
            ru[u]=0;
        }
        else if(op==3){
            cin>>u>>v;
            need+=w[u];
            ru[v]+=w[u];
        }
        else{
            cin>>u;
            need-=ru[u];
            need+=mx[u];
            ru[u]=mx[u];
        }
        if(need==sum) cout<<"YES"<<endl;
        else cout<<"NO"<<endl;
    }
    return 0;
}