hdu Train Problem I

这道题是道简单的栈模拟题，只要按照真实情况用栈进行模拟即可：

#include<stdio.h>
#include<string.h>
#include<stack>
using namespace std;
int main()
{
    int n, i, j, k, flag[];
    char s1[], s2[];
    stack <char> s;
    while(~scanf("%d %s%s",&n,s1,s2))
    {
        while(!s.empty())  s.pop(); //也可以不写这一句，把 stack <char> s; 就可以了
        memset(flag,-,sizeof(flag));
        j = k = ;
        for(i = ; i < n; i++)
        {
            s.push(s1[i]);
            flag[k++] = ;
            while(!s.empty() && s.top() == s2[j])
            {
                flag[k++] = ;
                s.pop();
                j++;
            }
        }
        if(j == n)
        {
            printf("Yes.\n");
            for(i = ; i < k; i++)
            {
                if(flag[i])
                    printf("in\n");
                else
                    printf("out\n");
            }
        }
        else
            printf("No.\n");
        printf("FINISH\n");
    }
    return ;
}