#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;


int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */
    string s;
    cin >> s;
    string res = "";
    res += s[0];

    for(long i = 1; i < s.size(); i++) {
        long count = 1;
        if(s[i - 1] != s[i])
            res += s[i];
        while(i<s.size() && s[i] == s[i - 1]) {
            count++;
            i++;
        }
        if(count != 1) {
            res += to_string(count);
            i--;
        }
    }
    cout << res << endl;
    return 0;
}