C. Heap Operations

http://codeforces.com/problemset/problem/681/C

题意：模拟优先队列；

坑：先判断是否空再判断front()是否满足条件，remove前要不为空

#include<algorithm>
#include<set>
#include<vector>
#include<queue>
#include<cmath>
#include<cstring>
#include<iostream>
#include<algorithm>
#include<set>
#include<vector>
#include<queue>
#include<cmath>
#include<cstring>
#include<sstream>
#include<cstdio>
#include<ctime>
#include<map>
#include<stack>
#include<string>
using namespace std;

#define sfi(i) scanf("%d",&i)
#define pri(i) printf("%d\n",i)
#define sff(i) scanf("%lf",&i)
#define ll long long
#define mem(x,y) memset(x,y,sizeof(x))
#define INF 0x3f3f3f3f
#define eps 1e-6
#define PI acos(-1)
#define lowbit(x) ((x)&(-x))
#define zero(x) (((x)>0?(x):-(x))<eps)
#define fl() printf("flag\n")
ll gcd(ll a,ll b){while(b^=a^=b^=a%=b);return a;}
const int maxn=1e6+9;
const int mod=1e9+7;

template <class T>
inline void sc(T &ret)
{
    char c;
    ret = 0;
    while ((c = getchar()) < '0' || c > '9');
    while (c >= '0' && c <= '9')
    {
        ret = ret * 10 + (c - '0'), c = getchar();
    }
}

struct A
{
    string s;
    int x;
}ans[maxn];
char str[maxn];
priority_queue<int,vector<int>,greater<int> >q;
int main()
{
    int cnt=0;
    int n;
    sfi(n);
    for(int i=0;i<n;i++)
    {
        scanf("%s",str);
        if(str[0]=='i')
        {
            int num;
            sfi(num);
            //cout<<num<<endl;
            q.push(num);
            ans[cnt].s=str;
            ans[cnt].x =num;
            //cout<<ans[cnt].s<<endl;
            cnt++;
        }
        else if(str[0]=='g')
        {
            int num;
            sfi(num);
            //cout<<num<<endl;
            //cout<<q.size()<<endl;
            while(!q.empty()&&q.top()<num)
            {
                //cout<<q.top()<<endl;
                ans[cnt++].s="removeMin";
                q.pop();
            }

            if(q.empty()||q.top()!=num)
            {
                q.push(num);
                ans[cnt].s="insert";
                ans[cnt].x=num;
                cnt++;
            }
            ans[cnt].s=str;
            ans[cnt].x=num;
            cnt++;
        }
        else
        {
            if(!q.empty())
                q.pop();
            else
            {
                ans[cnt].s="insert";
                ans[cnt++].x=0;
                //q.push(0);
            }
            ans[cnt++].s=str;
        }

    } pri(cnt);
        for(int i=0;i<cnt;i++)
        {
            if(ans[i].s[0]=='i')
            {
                cout<<ans[i].s<<" ";
                pri(ans[i].x);
            }
            else if(ans[i].s[0]=='g')
            {
                cout<<ans[i].s<<" ";
                pri(ans[i].x);
            }
            else
            cout<<ans[i].s<<endl;
        }
    return 0;
}