CCCPaste

Untitled

#include 
#include 
using namespace std;
void rec(int number) {
    if(number == 0) {
        return;
    }
    int last_digit = number % 10;
    if(last_digit == 9) {
        last_digit = 7;
    }
    rec(number / 10);
    cout << last_digit;
}
int main()
{
    int number;
    cin >> number;
    rec(number);
    cout << endl;
    return 0;
}