Str = list(input()) Str1=[] for ch in Str: Str1.append(ch) Flag=0 if not Str: print('') Flag = 1 n = len(Str) dp=[] for i in range(n): if Str[i]=='a': dp.append('a') else: if not dp&nbs***bsp;dp[-1]=='b': dp.append('b') else: ...