#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <iostream>
using namespace std;

const int N = 105;

int n;
char M[ N ];

int main( void ) {
	scanf( "%d%s", &n, M );
	for( int i = 0; i < n; i++ ) {
		int cnt = 1;
		while( i + 1 < n && M[ i ] == M[ i + 1 ] ) cnt++, i++;
		printf( "%c%d", M[ i ], cnt );
	}
	printf( "\n" );
	return 0;
}