hdu 1181: 变形课

#include <stdlib.h>
#include <strin
int ()
{
    freopen("Sample Input.txt","r",stdin);
    system("Color F0");
    char s[100];
    int i,j,k,len;
    int m[30][30];
    while (gets(s))
    {
        memset(m,0,sizeof(m));
        while (s[0]!='0')
        {
            len = strlen(s);
            m[s[0]-'a'][s[len-1]-'a'] = 1;
            gets(s);
        }
        for ( k = 0; k < 26; k++)
        {
            for ( i = 0; i < 26; i++)
            {
                if (i==k)
                    continue;
                for ( j = 0; j < 26; j++)
                {
                    if ( j==k || j==i )
                        continue;
                    if ( m[i][k] && m[k][j] ) m[i][j] = 1;
                }
            }
        
        if (m[1][12])
            printf("Yes.n");
        else
            printf("No.n");
    }
    getch();
    return 0;