剪刀石头布的问题 - 只有一半返回一个结果

Question

我是新来的Java并使用嵌套的if语句编写两个玩家的摇滚/纸/剪刀比赛任务。只有一半我的结果打印结果

该程序将所有组合的作品，当我使用“否则，如果（”石头“.equals（PLAYER1）&&‘纸’.equals（player2））”，而不是嵌套的if语句，但有嵌套IFS是栏目的一部分。

    Scanner in = new Scanner(System.in);

    System.out.print("Player 1, please choose rock, paper, or scissors: ");
    String player1 = in.next();         
    System.out.print("Player 2, please choose rock, paper, or scissors: ");
    String player2 = in.next(); 

    player1 = player1.toLowerCase();
    player2 = player2.toLowerCase();


    if (player1.equals(player2))
    {
        System.out.println("It's a tie!");
    }

    else if ("rock".equals(player1))    
    {
        if ("paper".equals(player2))
        {
            System.out.println("Paper covers rock - Player 2 wins!");
        }
    }

    else if ("rock".equals(player1))            
        {
        if ("scissors".equals(player2))     
        {
            System.out.println("Rock breaks scissors - Player 1 wins!");
        }
    }           

    else if ("paper".equals(player1))
    {
        if ("scissors".equals(player2))     
        {
            System.out.println("Scissors cut paper - Player 2 wins!");
        }
    }

    else if ("paper".equals(player1))
    {
        if ("rock".equals(player2))     
        {
            System.out.println("Paper covers rock - Player 1 wins!");
        }
    }       

    else if ("scissors".equals(player1))
    {
        if ("paper".equals(player2))        
        {
            System.out.println("Scissors cut paper - Player 1 wins!");
        }
    }
    else if ("scissors".equals(player1))
    {
        if ("rock".equals(player2))     
        {
            System.out.println("Rock breaks scissors - Player 2 wins!");
        }
    }

    else
    {
        System.out.println("Invalid input. Please try again using rock, paper, or scissors");
    }

    in.close();
    }

 }

我预计投入每个组合的输出，但剪刀石头VS，摇滚VS剪刀和纸VS摇滚不产生任何输出到控制台。

Answer 1

else if ("rock".equals(player1))    
{
    if ("paper".equals(player2))
    {
        System.out.println("Paper covers rock - Player 2 wins!");
    }
}
else if ("rock".equals(player1))            
    {
    if ("scissors".equals(player2))     
    {
        System.out.println("Rock breaks scissors - Player 1 wins!");
    }
}  

请注意，您有相同的检查两次。当第一之一为真，则只有该块将执行和下一else if...将被跳过。为了解决这个问题，只是做所有的检查在一个块player2的：

else if ("rock".equals(player1))    
{
    if ("paper".equals(player2))
    {
        System.out.println("Paper covers rock - Player 2 wins!");
    }
    else if ("scissors".equals(player2))     
    {
        System.out.println("Rock breaks scissors - Player 1 wins!");
    }
}  

你也应该了解switch声明，可以提供一种替代解决问题的方法。