hoj 2578 Super_Stack 模拟栈

/*



用结构体数组模拟栈，结构体中保存当前min与max的值



*/

#include <iostream>

#include <cstdio>

#include <cstring>



using namespace std;



const int X = 65537;



int n,top;



struct node

{

    int max,min;

}stack[X];



int main()

{

    freopen("sum.in","r",stdin);

    char s[10];

    int x;

    int ncase = 0;

    while(cin>>n,n)

    {

        printf("Case %d\n",++ncase);

        top = 0;

        for(int i=0;i<n;i++)

        {

            scanf("%s",s);

            if(s[0]=='m')

            {

                if(!top)

                    printf("null\n");

                else

                {

                    if(s[1]=='a')

                        printf("%d\n",stack[top-1].max);

                    else

                        printf("%d\n",stack[top-1].min);

                }

            }

            else

            {

                if(s[1]=='o')

                {

                    if(top)

                        top--;

                }

                else

                {

                    scanf("%d",&x);

                    if(top)

                    {

                        stack[top].max = max(x,stack[top-1].max);

                        stack[top].min = min(x,stack[top-1].min);

                    }

                    else

                        stack[top].min = stack[top].max = x;

                    top++;

                }

            }

        }

    }



    return 0;

}