发布时间: 2018年12月8日 20:11 最后更新: 2018年12月8日 20:12 时间限制: 1000ms 内存限制: 512M
Given a password $s$ with a length of $n$, we want to figure out how many different characters there are in the password.
The first line of input contains an integer $n(6 \le n \le 16)$, representing the length of the password.
The following line contains the string $s$ with the length of $n$, consisting of only visible characters(with ASCII codes between 33 and 126).
Display the number of different characters.
There are 12 different characters in the first sample, that is, 'W','e','l','c','o','m','T','F','D','U','P' and 'C'.
All characters in the second sample are different.