#include <iostream>
#include <vector>
#include <string>
#include <cmath>
#include <set>
using namespace std;


int main() {
    string s;
    cin >> s;
    
    for(int i = 0; i < s.size(); i++) {
        int j = i;
        int cnt = 0;
        while(j < s.size() and s[i] == s[j]) {
            cnt++;
            j++;
        }
        cout << cnt << s[i];
        i = j - 1;
    }
    
    return 0;
}
//  1