我如何显示飞机座位表？

Question

This is my code:

import java.util.Scanner;

public class AirlineReservation {

    public static void main(String[]args) {
        System.out.println("Enter n:");
        Scanner scanner = new Scanner(System.in);

        int n = scanner.nextInt();
        int[][] airplane = new int[n][4];

        for(int i = 1; i < 4; i++) {
            System.out.printf("%3d\t", i);
        }

        for(int j = 0; j <= n; j++) {
            System.out.println((j) + " -" + "       -" + "       -" + "      -");
        } 
    }
}

What I want is to have four numbers display on top (which it does), have the user enter some number and have that be the number of rows (which it does), and "-" for each open section.

I'm not sure how to do this and I have some of my j int on the first line which I do not want. Can someone give me a hand with this?

This is the output output:

Enter n:
5
  1       2       3      4  
1 -       -       -      -

2 -       -       -      -

3 -       -       -      -

4 -       -       -      -

5 -       -       -      -

Answer 1

You have a couple of errors in your code.

First for loop should start at 1 end at 4 (both included), so I added an =.

for (int i = 1; i <= 4; i++) {
    System.out.printf("%3d\t", i);
}

Second loop should start from 0 (included) and end at n (excluded) or from 1 to n (both included). So I changed it to the following. In addition for each row you have to present all the seats (4). So this new code:

for (int row = 1; row <= n; row++) {
    System.out.print(j); // Print the number of row
    for (int seat = 1; seat <= 4; seat++) {
        System.out.print(" -"); // Print each seat
    }
    System.out.println(""); // Go to the next line
}

But this only prints the empty plane. The best should be print the current plane configuration (with - for empty seat and x for non empty seat). It is possible with the following code assuming that airplane[row][seat] is 0 for a free seat and a different value for occupied seat:

for (int row = 1; row <= n; row++) {
    System.out.print(j); // Print the number of row
    for (int seat = 1; seat <= 4; seat++) {
        System.out.print(" "); // Print separator
        if (airplane[row - 1][seat - 1] == 0) {
            System.out.print("-");
        } else {
            System.out.print("X");
        }
    }
    System.out.println(""); // Go to the next line
}

Answer 2

Just control your fomatting:

public static void main(String[]args) {
    System.out.println("Enter n:");
    Scanner scanner = new Scanner(System.in);

    int n = scanner.nextInt();
    int[][] airplane = new int[n][4];

    for(int i = 1; i <= 4; i++) {
        System.out.printf("\t%d\t", i);
    }
    System.out.println("");

    for(int j = 1; j <= n; j++) {
        System.out.printf("%d", j);
        for (int k = 1; k <= 4; k++) {
            System.out.print("\t-\t");
        }
        System.out.println("");
    } 
} 

There's probably a much clean way of doing this, but it does produce the output you're wanting.

Results:

Answer 3

Rewrite you coded as:

import java.util.Scanner;

public class AirlineReservation {

    public static void main(String[]args) {
        System.out.println("Enter n:");
        Scanner scanner = new Scanner(System.in);

        int n = scanner.nextInt();
        int[][] airplane = new int[n][4];

        for(int i = 1; i <= 4; i++) {//Change here.
            System.out.printf("%3d\t", i);
        }
        System.out.println();//Change here.

        for(int j = 1; j <= n; j++) {
            System.out.println((j) + " -" + "       -" + "       -" + "       -");//change Here.
        } 
    }
}