题解 | 字符个数统计
字符个数统计
https://www.nowcoder.com/practice/eb94f6a5b2ba49c6ac72d40b5ce95f50
#include <iostream>
#include <string>
#include <set>
int main(){
std::string s;
std::cin >> s;
std::set<char> subs(s.begin(), s.end());
std::cout << subs.size();
return 0;
}
