word = input().upper() cnt = dict() for i in word: if i in cnt: cnt[i] += 1 else: cnt[i] = 1 max = max(cnt.values()) rst = list() for k, v in cnt.items(): if v == max: rst.append(k) if len(rst) == 1: print(rst[0]) else: print('?') 1. 2. 1 3. 6 4. 4 5. 1 6. 4 7. 3 8. 1