/* hex2rle.c (CC0/Public Domain)

Usage:
    hex2rle < input_file.hex >> out.hex
*/
#include <stdio.h>

int main() {
    unsigned int val = 0, lval = 0, nval = 0;

    while (scanf("%2x", &val) == 1) {
        if ((nval && val != lval) || nval == 255) {
            printf("%02x%02x", nval, lval);
            nval = 0;
        }
        nval++;
        lval = val;
    }
    if (nval) printf("%02x%02x", nval, lval);

    return 0;
}