2016暑假多校联合---Joint Stacks （STL）

#include <iostream>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <stack>
#include <queue>
using namespace std;
struct Node
{
    int x;
    int t;
};
stack<Node*>A,B,C,D;

int main()
{
    int N,Case=1;
    char s[10];
    char x;
    int c;
    while(scanf("%d",&N)&&N)
    {
        printf("Case #%d:\n",Case++);
        for(int i=1;i<=N;i++)
        {
            scanf("%s",s);
            if(s[1]==‘u‘)
            {
                scanf(" %c",&x);
                scanf("%d",&c);
                Node* a=new Node();
                a->x=c;
                a->t=i;
                if(x==‘A‘)
                    A.push(a);
                else
                    B.push(a);
            }
            else if(s[1]==‘o‘)
            {
                scanf(" %c",&x);
                if(x==‘A‘)
                {
                    if(A.empty())
                    {
                        printf("%d\n",C.top()->x);
                        C.pop();
                    }
                    else
                    {
                        printf("%d\n",A.top()->x);
                        A.pop();
                    }
                }
                else
                {
                    if(B.empty())
                    {
                        printf("%d\n",C.top()->x);
                        C.pop();
                    }
                    else
                    {
                         printf("%d\n",B.top()->x);
                         B.pop();
                    }
                }
            }
            else if(s[1]==‘e‘)
            {
                scanf(" %c",&x);
                scanf(" %c",&x);
                while(!A.empty()&&!B.empty())
                {
                    if(A.top()->t>B.top()->t)
                    {
                        D.push(A.top());
                        A.pop();
                    }
                    else
                    {
                        D.push(B.top());
                        B.pop();
                    }
                }
                while(!A.empty())
                {
                    D.push(A.top());
                        A.pop();
                }
                while(!B.empty())
                {
                    D.push(B.top());
                        B.pop();
                }
                while(!D.empty())
                {
                    C.push(D.top());
                    D.pop();
                }
            }
        }
    }
    return 0;
}