https://www.luogu.com.cn/record/123027155

为什么 T 了？我离 AK 就差这一个点啊……

#include<iostream>
#include<queue>
#define int long long
using namespace std;
int c,t,s[200010];
int head=1,tail=0;
struct node{int x,id,left;}a[200010];
bool operator<(const node &x,const node &y){
    return x.x<y.x;
}
priority_queue<node>q;
signed main()
{
    cin>>c>>t;
    while(t--)
    {
        int op;
        cin>>op;
        if(op==1)
        {
            int x;
            cin>>x;
            a[++tail]={x,tail,x},s[tail]=s[tail-1]+x;
            q.push({x,tail,x});
        }
        if(op==2)
        {
            int x;
            cin>>x;
            while(a[head].left<=x)x-=a[head].left,head++;
            a[head].left-=x;
        }
        if(op==3)
        {
            int x;
            cin>>x;
            if(x<=a[head].left)
                cout<<a[head].x-a[head].left+x<<endl;
            else
            {
                x-=a[head].left;
                int l=head,r=tail,pos=0;
                while(l<=r)
                {
                    int mid=(l+r)/2;
                    if(s[mid]-s[head]<x)l=mid+1,pos=mid;
                    else r=mid-1;
                }
                cout<<x-(s[pos]-s[head])<<endl;
            }
        }
        if(op==4)
        {
            while(q.top().id<head)q.pop();
            cout<<q.top().x<<endl;
        }
    }
    return 0;
}