[恢]hdu 1181

2011-12-26 00:07:58

地址：http://acm.hdu.edu.cn/showproblem.php?pid=1181

题意：中文，水。

mark：bfs练习。

代码：

# include <stdio.h>
# include <string.h>


char str[200] ;
int graph[30][30] ;
int visited[30] ;
int q[30] ;


int gao()
{
    int i, ch ;
    int front = 0, rear = 0 ;
    q[rear++] = 1 ;
    while (front != rear)
    {
        ch = q[front++] ;
        if (ch == 'm'-'a') return 1 ;
        for (i = 0 ; i < 26 ; i++)
        {
            if (graph[ch][i]==1  && visited[i] == 0)
            {
                visited[i] = 1 ;
                q[rear++] = i ;
            }
        }
    }
    return 0 ;
}


void init()
{
    memset (graph, 0, sizeof(graph)) ;
    memset (visited, 0, sizeof(visited)) ;
}


int main ()
{
    while  (gets (str))
    {
        if (strcmp(str, "0") == 0)
        {
            puts (gao() ? "Yes." : "No.") ;
            init() ;
        }
        else
        {
            graph[str[0]-'a'][str[strlen(str)-1]-'a'] = 1 ;
        }
    }
    return 0 ;
}