题解 | #提取不重复的整数#

//https://www.nowcoder.com/practice/253986e66d114d378ae8de2e6c4577c1?tpId=37&tqId=21232&rp=1&ru=/exam/oj/ta&qru=/exam/oj/ta&sourceUrl=%2Fexam%2Foj%2Fta%3FtpId%3D37&difficulty=undefined&judgeStatus=undefined&tags=&title=

#include <iostream>
#include <algorithm>

using namespace std;

bool used[58];

int main() {
    string s;

    while (cin >> s) {
        reverse(s.begin(), s.end());

        for(auto c:s){
            if(!used[c]){
                used[c] = 1;
                cout << c;
            }
        }

         cout << endl;
    }
}