s = "maria.ozawa.mp9" for i in range(len(s)): if s[i] == ".": dot_index = i print(s[:dot_index]) #optimized solution dot_index = 0 for i in range(len(s) - 1,-1,-1): if s[i] == ".": dot_index = i break print(s[:dot_index]) #one_liner solution print(s[:s.rfind(".")])