JAVA陣列+掃描儀錯誤？

Question

我正在做一些程序，但很難使用陣列和掃描儀。 我希望用戶輸入他玩過的游戲數，然后輸入他完成的游戲數。 之后，我要他輸入完成每場比賽所花費的時間。

我對此並不陌生，現在真的很困。 我需要獲取用戶完成游戲所花費的每一次價值，因為以后需要將一些統計信息應用於該值。

我遇到2個錯誤！

這是我的一些代碼：

import java.util.Scanner;
public class games {

    public static void main(String args[]) {
        Scanner input = new Scanner(System.in);
        System.out.println("How many games have you played? (Limit of 10) : ");
        int gamesplayed = input.nextInt();input.nextLine();
        while ( gamesplayed < 0 || gamesplayed> 10 ) {
             System.out.println("This number is invalid!");
             System.exit(0);
        }
        System.out.println("How many of these games have you finished? (Limit of 10) : ");
        int finishedgames = input.nextInt();input.nextLine();
        while ( finishedgames < 0 || finishedgames > 10 || gamesplayed < finishedgames ) {                
             System.out.println("This number is invalid!");
             System.exit(0);
        }
        int game = 1;
        int list[]=new int[game];
        while ( finishedgames+1 != game) 
        {
            System.out.print("How many time you took to finish your game " + game);System.out.println("?");
            list[game] = input.nextInt();
            input.nextLine();
            ++game;
        }
    }
}

非常感謝您的幫助！

Answer 1

首先，請使用if語句，而不是兩個while循環。

問題是這一行： int list[]=new int[game];

上一行（ int game=1; ）將此變量的值設置為1，因此您的int數組只能存儲一個元素。

您應該使用int list[]=new int[finishedgames]; 代替。

另外，考慮用for循環替換最后一個while循環。

編輯：

import java.util.Scanner;
public class games {
public static void main(String args[]) {
    Scanner input = new Scanner(System.in);
    System.out.println("How many games have you played? (Limit of 10) : ");
    int gamesplayed = input.nextInt();input.nextLine();
    if ( gamesplayed < 0 || gamesplayed> 10 ) {
         System.out.println("This number is invalid!");
         System.exit(0);
    }
    System.out.println("How many of these games have you finished? (Limit of 10) : ");
    int finishedgames = input.nextInt();input.nextLine();
    if ( finishedgames < 0 || finishedgames > 10 || gamesplayed < finishedgames ) {                
         System.out.println("This number is invalid!");
         System.exit(0);
    }
    int list[]=new int[finishedgames];
    for (int i=0;i<list.length;i++) {
        System.out.println("How many time you took to finish your game " + (i+1) + "?");
        list[i] = input.nextInt();
        input.nextLine();
    }
}
}

Answer 2

import java.util.Scanner;
public class games {
      public static void main(String args[]) {
       Scanner input = new Scanner(System.in);
       System.out.println("How many games have you played? (Limit of 10) : ");
       int gamesplayed = input.nextInt();
       while ( gamesplayed < 0 || gamesplayed> 10 ) {
           System.out.println("This number is invalid!");
           gamesplayed = input.nextInt();
       }
       System.out.println("How many of these games have you finished? (Limit of 10) : ");
       int finishedgames = input.nextInt();
       while ( finishedgames < 0 || finishedgames > 10 || gamesplayed < finishedgames ) {
             System.out.println("This number is invalid!");
             finishedgames = input.nextInt();
       }
       int game = 1,Rem =finishedgames-gamesplayed ;
       int list[]=new int[Rem+1];
       while (Rem!=0) {
            System.out.println("How many time you took to finish your game " +game+"?");
            list[game] = input.nextInt();
            ++game;
            --Rem;
       }
   } 

}

Answer 3

public class Games {

public static void main(String args[]) {
    Scanner input = new Scanner(System.in);

    System.out.println("How many games have you played? (Limit of 10) : ");
    String nextLine = input.nextLine();

    int gamesplayed = toInteger(nextLine);

    while (gamesplayed < 0 || gamesplayed > 10) {
        System.out.println("Wrong input, try again.");
        gamesplayed = toInteger(input.nextLine());
    }

    System.out.println(String.format(
            "How many of these games have you finished? (Limit of %d) : ",
            gamesplayed));
    nextLine = input.nextLine();
    int finishedgames = toInteger(nextLine);
    while (finishedgames < 0 || finishedgames >  gamesplayed ) {
        System.out.println("Wrong input, try again.");
        finishedgames = toInteger(input.nextLine());;
        if (finishedgames > gamesplayed) {
            System.out.print("Invalid Entry. ");
        }
    }

    int list[] = new int[finishedgames];
    for (int i = 0; i < finishedgames; i++){

        System.out.println(String.format("How many time you took to finish your game %d?", i + 1));
        int val = toInteger(input.nextLine());
        while (val == Integer.MAX_VALUE) {
            System.out.println("Wrong input, try again.");
            val = toInteger(input.nextLine());
        }
        list[i] = val;  
    }

    for (int i = 0; i < list.length; i++) {
        System.out.println(String.format("list[%d] = %d", i, list[i]));
    }
}

// Helper method that converts user entry to integer value
private static int toInteger(String nextLine) {
    try {
        return Integer.parseInt(nextLine);
    } catch (NumberFormatException e) {
        return  Integer.MAX_VALUE;
    }
}

}