hdu 5349 MZL's simple problem(15多校第五場1007)

//15多校第三場1007
//hdu 5349
//set水過
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<queue>
#include<vector>
#include<set>
using namespace std;
const long long mod=1e9+7;
const int INF=0x7fffffff;
typedef long long LL;
const int maxn= 101000,maxm=6*100010;
set<int>S;
int main(){
    int n;
    int minn=INF,maxx=-INF;
    while(scanf("%d",&n)!=EOF){
        int op,x;
        S.clear();
        for(int i=0;i<n;i++){
            scanf("%d",&op);
            if(op==1){
                scanf("%d",&x);
                S.insert(x);
                minn=min(x,minn);
                maxx=max(x,maxx);
            }
            else if(op==2){
                if(minn==INF)continue;
                x=*S.begin();
                S.erase(S.begin());
                if(S.size()!=0)minn=*S.begin();
                else minn=INF,maxx=-INF;
            }
            else {
                if(maxx==-INF){
                    printf("0\n");
                    continue;
                }
                printf("%d\n",maxx);
            }
        }
    }
    return 0;
}