洛谷P3378 【模板】堆

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cstring>
using namespace std;
typedef long long ll;
const int N=1e6+5;
inline int read(){
    char c=getchar();int x=0,f=1;
    while(c<‘0‘||c>‘9‘){if(c==‘-‘)f=-1;c=getchar();}
    while(c>=‘0‘&&c<=‘9‘){x=x*10+c-‘0‘;c=getchar();}
    return x*f;
}
int n,op,x;
int a[N],len=0;
inline bool cmp(int a,int b){return a>b;}
int main(){
    n=read();
    for(int i=1;i<=n;i++){
        op=read();
        if(op==1){
            a[len++]=read();
            push_heap(a,a+len,cmp);
        }else if(op==2) printf("%d\n",a[0]);
        else pop_heap(a,a+len,cmp),len--;
    }
}