#include <stdio.h>
#include <string.h>
int main()
{
    char a[] = "aabcccccaaa";
    int count = 1;
    for (int i = 0; a[i] != '\0'; i++)
    {
        for (int j = i + 1; a[j] != '\0'; j++)
        {
            if (a[j] == a[i])
            {
                count++;
            }
            else
            {
                break;
            }
        }
        printf("%c%d", a[i], count);
        i += (count - 1);
        count = 1;
    }
}