tj

#include <string>
#include <iostream>

using namespace std;

string number;

int main( ) {
    cin >> number;
    
    if (number == "5000") {
        cout << '5' << endl;
        return 0;
    } else {
        for (int i = number . length() - 1 ; i >= 0 ; i--) {
            cout << number[i];
        }
    }

    return 0;
}