Question

我是Java新手，正在构建Rock，Paper，Scissors游戏。我试图找出为什么我的while语句在第一次尝试时无法识别正确的输入。感谢您提前提供的任何帮助。

`
import java.util.Scanner; import java.util.Random;

public class RPC
{
public static void main (String[] args)
{
 //Utilities
Scanner in = new Scanner (System.in);
Random r = new Random ();

//variables

int userwins =0;
int computerwins =0;
int numberofgames = 0;
int randomnumber = 0;
String userpick = "";
String computerpick = "";


// Welcome statement
System.out.println("Welcome to Rock, Paper, Scissors!");


//Get the number of games from the user
System.out.println("Please enter the number of rounds you would like to play:");
numberofgames = in.nextInt();

//Flush the buffer
in.nextLine();


// Game play for the number of times the user specified.

for (int i=1; i <= numberofgames; i++)
  {


  System.out.println("Rock, Paper, or Scissors?:");
  userpick = in.nextLine();

  while (!userpick.equalsIgnoreCase("rock") && !userpick.equalsIgnoreCase("paper") && !userpick.equalsIgnoreCase("scissors"));
  {
     System.out.println("Sorry," +userpick+ " is not a valid entry.Please enter Rock, Paper, or Scissors.");
     userpick = in.nextLine();

  }

  //Make a random choice
  randomnumber = r.nextInt(3)+1; 

  if (randomnumber == 1)
  {
  computerpick = ("rock");
  }
  if (randomnumber == 2)
  {
  computerpick = ("paper");
  }
  if (randomnumber == 3)
  {
  computerpick = ("scissors");
  }

  //Decide who wins the round

  if (userpick.equalsIgnoreCase("rock")) {
     if (computerpick.equalsIgnoreCase("scissors"))
        System.out.println("Rock beats scissors. You win!");
else if (computerpick.equalsIgnoreCase("paper"))
        System.out.println("Paper beats rock. The computer wins!");
    else
        System.out.println("Computer chooses rock. It's a tie.");
} 
else if (userpick.equalsIgnoreCase("paper")) {
     if (computerpick.equalsIgnoreCase("scissors"))
        System.out.println("Scissors beats paper. The computer wins!");
else if (computerpick.equalsIgnoreCase("rock"))
        System.out.println("Paper beats rock. You win!");
    else
        System.out.println("Computer chooses paper. It's a tie.");
} 
else if (userpick.equalsIgnoreCase("scissors")) {
     if (computerpick.equalsIgnoreCase("rock"))
        System.out.println("Rock beats scissors. The computer wins!");
else if (computerpick.equalsIgnoreCase("paper"))
        System.out.println("Scissors beats paper. You win!");
    else
        System.out.println("Computer chooses scissors. It's a tie.");

  }
 }

} }`

Answer 1

删除终止while语句

的分号

while (...);
           ^

Answer 2

在for循环后删除分号。 while / for / if之后的分号表示它是一个空语句，这意味着带有括号的下一个代码块就像一个块一样，无论条件是否成立，它都会被评估。

Answer 3

分号通常在java中结束一行。为了使while循环运行，您需要删除半列。

不等于while循环中的条件

3 个答案: