#include <iostream>
#include <cmath>
using namespace std;
int main(void){
    int number,b,s,g;
    cin >> number;
    while(number){
        g = number % 10;
        number /= 10;
        s = number % 10;
        number /= 10;
        b = number % 10;
        number /= 10;
    }
    for(int i = b;i > 0;i--)
        cout << 'B';
    for(int i = s;i > 0;i--)
        cout << 'S';
    for(int i = 1;i <= g;i++)
        cout << i;

    return 0;
}