题解 | #提取不重复的整数#

#include <iostream>
#include <set>
using namespace std;

int ReserveandRemoveDuplicates(int num) {
    set<int> seen;
    int result = 0;

    while(num>0) {
        int digit = num % 10;
        if(seen.find(digit) == seen.end()) {
            seen.insert(digit);
            result = result * 10 + digit;
        }
        num = num / 10;
    }

    return result;
}
int main() {
    int num;
    while (cin >> num) { // 注意 while 处理多个 case
        cout << ReserveandRemoveDuplicates(num) << endl;
    }
}
// 64 位输出请用 printf("%lld")