MI2019-s3e1.cpp

#include <iostream>
using namespace std;


void Impare(int &n) {

        int new_n, p = 1;

        while (n > 0) {

                int new_digit = n % 10;
                if (n % 2 == 1) {
                        new_digit--;
                }

                new_n = new_digit * p + new_n;
                p = p * 10;
                n = n / 10;
        }

        n = new_n;
}


int main() {

        int n;

        cin >> n;
        Impare(n);

        cout << n << endl;

        return 0;
}