Python3 石头 剪刀 布游戏，分别用A B C表示。胜负规则为：A＞B，B＞C，C＞A。本场中有且仅有一种出拳形状优于其他形状，则为胜利者，否则认为平局。键盘输入信息：每个玩家信息为一行，数量不超过100，信息两个字段，用空格隔开，玩家ID：一个仅有英文和数字构成，出拳形状用A，B，C表示。输出：赢家ID列表（一个或多个），每个ID一行，按字符串升序，如果没有赢家，输出'NuLl'字符串）

```python def judge_winner(player1, player2): if player1[1] == player2[1]: return None # 平局 if (1[1] == 'A' and player2[1] == 'B') or (player1[1] == 'B' and player2[1] 'C') or (player1[1 == 'C' and player2[1] == 'A'): return player1[0] else: return player2[0] players = [] True: try: player = input().split() len(player) == 0: break players.append(player) except EOFError: break winners = set() for i in range(len(players)): for j in range(i 1, len(players)): winner = judge_winner(players[i], players[j]) if winner: winners.add(winner) if winners for id in sorted(winners): print(id) else: print('NuLl') ``` 运行示例： ``` A A B B C C A B B C A ``` 输出： ``` A B C ```