#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<algorithm>
#define M 100003
int n,s1,L1,f;
char str[100000],ch[27];
int main()
{
int i;
while(scanf("%d %s",&n,str)!=EOF&&n)
{
memset(ch,0,sizeof(ch));
s1=0;
L1=strlen(str);
for(i=0;i<L1;i++)
{
if(ch[str[i]-'A'+1]==0&&n>0) //ch[i]该数组的下标与大写的26个字母一一对应,用来记录每位游客来去的状态
{
ch[str[i]-'A'+1]=1; //ch[i]从0变到1说明该游客刚来,并且有座位
n--;
}
else if(ch[str[i]-'A'+1]==0&&n==0)
{
s1++;
ch[str[i]-'A'+1]=2; //ch[i]从0变到2说明该游客刚来,但没座位
}
else if(ch[str[i]-'A'+1]==1)
{ //ch[i]从1变到0说明该有座位的游客要离开
ch[str[i]-'A'+1]=0;
n++;
}
}
if(s1)printf("%d customer(s) walked away.\n",s1);
else printf("All customers tanned successfully.\n");
}
system("pause");
return 0;
}