冲洗缓冲液不正确

Question

所以我的代码全部正常工作，但是它没有计算第一轮，所以我需要首先刷新缓冲区。所以我试着放置：

in.nextln（）;清除缓冲区但它仍然希望有用户输入，因此它会更加混乱。

我试着将它放在这个位置：

 //Gets the users play of rock paper scissors
 System.out.println("Your play:");
 //try adding in.nextLine(); here to flush buffer
 userPlay = in.nextLine();

以下是我的完整代码，可帮助您更好地了解我正在做的事情：

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


public class final5
{ 
   public static void main(String[] args) 
   { 
      //Intitalizing all variables
      String userPlay; 
      String computerGuess = ""; 
      int numGames = 0;   
      int userWins = 0;
      int computerWins = 0;
      int computerRandom; //Makes the computer have random guess 

      String response; 
      Scanner in = new Scanner(System.in); 
      Random r = new Random(); 

      System.out.println("Welcome to Rock Paper Scissors");
      System.out.println("Number of rounds:");
      numGames = in.nextInt();

      //Checks to make sure num of games is valid/odd
      while ( numGames % 2 == 0 )
      {
         System.out.println("Please ensure your number is odd, and try again:");
         numGames = in.nextInt();
      }  


      in.nextLine();

      System.out.println(); 
      System.out.println("To play, please use the following inputs: (Rock = R, Paper = p, Scissors = s)");



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

         //Gets the users play of rock paper scissors
         System.out.println("Your play:");
         userPlay = in.nextLine();

         while (!userPlay.equalsIgnoreCase("R") && !userPlay.equalsIgnoreCase("P") && !userPlay.equalsIgnoreCase("S"))
         {
           System.out.println("Sorry, that is invalid. Please enter a a valid entry: Rock (R), Paper (P), Scissors (s)");
           userPlay = in.nextLine();
         }


         //We can intialize the userplay to all cap to make the code easier to read lower      
         userPlay = userPlay.toUpperCase(); 


          computerRandom = r.nextInt(3)+1;
          //Grabs a random number from random generator and italizes it to play rock, paper, or scissors
          if (computerRandom == 1) computerGuess = "R"; 
          else if (computerRandom == 2) computerGuess = "P"; 
          else if (computerRandom == 3) computerGuess = "S"; 


          if (userPlay.equals(computerGuess))
          { 
             System.out.println("You guys both tied, try again!");
             numGames++;
          }
          //Both tie no win for either

          if (userPlay.equals("R")) 
          {
             if (computerGuess.equals("S")) 
             {
                System.out.println("You won, computer had scissors.");
                ++userWins;
             }
          }
          //If user is rock and beats scirssors
          if (userPlay.equals("S"))
          {
            if (computerGuess.equals("P"))
            {
               System.out.println("You win, computer had paper!");
               ++userWins;
            }

          }
          else if (computerGuess.equals("P")) 
          {
                  System.out.println("You lost, computer had paper."); 
                  ++computerWins;
          }

          else if (userPlay.equals("P")) 
          {
             if (computerGuess.equals("S"))
             { 
               System.out.println("You lost, computer had scissors.");
               ++computerWins;
             }
          }

          else if (computerGuess.equals("R"))
          {
            System.out.println("You win, computer had rock."); 
            ++userWins;
          }

          else if (userPlay.equals("S")) 
          {
               if (computerGuess.equals("P")) 
               {
                  System.out.println("You win, computer had paper.");
                  ++userWins;
               }
          }

          else if (computerGuess.equals("R"))
          { 
            System.out.println("You lose, computer had rock."); 
            ++computerWins;     
          }     

       }//end of for loop

       //Gives total wins/loses and dermines winner  
       if(userWins > computerWins)
       {
         System.out.println();
         System.out.println("Your total wins: " +userWins );
         System.out.println("Total Computer Wins: " + computerWins );

         System.out.println("You have won the computer, congrats!");
       }

       if(userWins < computerWins)
       {
         System.out.println();
         System.out.println("Your total wins: " +userWins );
         System.out.println("Total Computer Wins: " + computerWins );

         System.out.println("Magically the computer won, nice try!");
       }


     }//end of main code
}//end of program

此外，当我清空缓冲区时，它不会在最后添加总胜利，让用户知道他们是赢还是输。