string = input() counter = 1 for i in range(len(string)): if string[i] == string[i+1]: counter += 1 else: print(string[i] + str(counter), end='') counter = 1
aaaabbcaa
a4b2c1
Traceback (most recent call last): File "./prog.py", line 5, in <module> IndexError: string index out of range