Still cannot find the bug. Need help to debug

Question about the task

Under discussion

I tested the input number from 1 to 5 without any error. Still, I cannot go through the validation and I cannot figure out what is wrong. The result looks like ok, I got the n x n array initiated with '#". I appreciate any help to debug it.

Let's create a program to generate square chessboards with a given dimension.
In the Solution class, you have a two-dimensional array of characters (the array field). Requirements:

Read a number from the keyboard. This will be the dimension of our board (the length of a side);
Initialize the array variable with the appropriate value;
"Paint" the array to obtain a checkerboard pattern (black cells - '#', white - ' '). Start the pattern by putting a '#' in the top left corner of the array;
Display the array on the screen as in the example (each row on a separate line).

Example output for number 5:
# # # # # # # # # # # # #

Requirements:

The program needs to read a number from the keyboard.
The array field must be initialized with an appropriately-sized array.
The array must be filled as outlined in the task conditions.
The program needs to display the elements of the array on the screen (see the example in the task conditions).

package en.codegym.task.jdk13.task06.task0634; import java.util.Scanner; /* Chess board */ public class Solution { public static char[][] array; public static void main(String[] args) { Scanner scanner = new Scanner(System.in); int n = scanner.nextInt(); array = new char[n][n]; for (int i = 0; i < n; i+=2) { for (int j = 0; j < n; j+=2) { array [i][j] = '#'; } } for (int i = 1; i < n; i+=2) { for (int j = 1; j < n; j+=2) { array[i][j] = '#'; } } for (int i = 0; i < n; i+=2) { for (int j = 1; j < n; j+=2) { array[i][j] = ' '; } } for (int i = 1; i < n; i+=2) { for (int j = 0; j < n; j+=2) { array[i][j] = ' '; } } for (int i = 0; i < n; i++) { for (int j = 0; j < n; j++) { System.out.print(array[i][j]); } System.out.println(" "); } } }

Comments (4)

Popular
New
Old

You must be signed in to leave a comment

Lisa L

Level 47 , Nuremberg, Germany

17 March 2022, 23:55

When I eg. enter 5 your program prints lines with 6 chars. #_#_#_ _#_#__ .. An easier approach would be to use a boolean. If the boolean is true, print one color, if false, the other. Then switch the boolean. That needs only one loop and no array.

boolean isWhite = false;
for (int i = 0; i < n; i++) {
    for (int j = 0; j < 5; j++) {
        System.out.print(isWhite ? " " : "#");
        isWhite = !isWhite;
    }
    System.out.println();
}

Roberto Fernandes

Level 10 , Vinhedo, Brazil

18 March 2022, 12:45

Thanks Lisa for you help. MfG

Siyanda Dlamini

Level 7 , Durban, South Africa

19 March 2022, 19:45

Wow this is amazing code Lisa. Thank you very much.

Lisa L

Level 47 , Nuremberg, Germany

19 March 2022, 20:47

hmm.., when looking at it again it needs another boolean to work with even numbers, too ...

boolean isEven = n % 2 == 0;
boolean isWhite = false;

for (int i = 0; i < n; i++) {
    for (int j = 0; j < n; j++) {
        System.out.print(isWhite ? " " : "#");
        isWhite = !isWhite;
    }
    if (isEven)
        isWhite = !isWhite;
    System.out.println();
}