# include & ltstdio.h & gt
# include & ltstring.h & gt
void main()
{
char s1[100]={'\0'},S2[100]= { ' \ 0 ' };
做{
if(strlen(s1)>strlen(s2))
strcpy(s2,s 1);
gets(s 1);
}while(!strstr(s1," stop "));
Printf("最長字符串為:%s ",S2);
}