poj 1250

        本来用cin cout输入输出，可不知道怎么弄得cin was not declared in this scorpe，怎么调都不行，郁闷...

#include<iostream>
#include<cstdio>
#include<cstring>
int main(){
    int n, d ;
    char a[100] ;
    bool v[100], e[100] ;
    while(scanf("%d", &n)!=EOF&&n){
        scanf("%s", &a) ;
        int b=0 ;
        memset(v,0,sizeof(v)) ;
        memset(e,0,sizeof(e)) ;
        for(int i=0; i<strlen(a); i++){
            d = a[i]-'A' ;
            if(!v[d]){
                v[d] = true ;
                if(n>0){
                    n -- ;
                    e[d] = true ;
                }
                else b++ ;
            }
            else if(e[d]) n ++ ;
        }
        if(b==0)
            printf("All customers tanned successfully.\n") ;
        else
            printf("%d customer(s) walked away.\n", b) ;
        }
    return 0 ;
}