How to print a two dimensional array?

Question

I have a [20][20] two dimensional array that I've manipulated. In a few words I am doing a turtle project with user inputting instructions like pen up = 0 and pen down = 1. When the pen is down the individual array location, for instance [3][4] is marked with a "1".

The last step of my program is to print out the 20/20 array. I can't figure out how to print it and I need to replace the "1" with an "X". The print command is actually a method inside a class that a parent program will call. I know I have to use a loop.

public void printGrid() {     System.out.println... } 

Answer 1

you can use the Utility mettod. Arrays.deeptoString();

 public static void main(String[] args) {     int twoD[][] = new int[4][];      twoD[0] = new int[1];      twoD[1] = new int[2];      twoD[2] = new int[3];      twoD[3] = new int[4];       System.out.println(Arrays.deepToString(twoD));  } 

Answer 2

public void printGrid() {    for(int i = 0; i < 20; i++)    {       for(int j = 0; j < 20; j++)       {          System.out.printf("%5d ", a[i][j]);       }       System.out.println();    } } 

And to replace

public void replaceGrid() {    for (int i = 0; i < 20; i++)    {       for (int j = 0; j < 20; j++)       {          if (a[i][j] == 1)             a[i][j] = x;       }    } } 

And you can do this all in one go:

public void printAndReplaceGrid() {    for(int i = 0; i < 20; i++)    {       for(int j = 0; j < 20; j++)       {          if (a[i][j] == 1)             a[i][j] = x;          System.out.printf("%5d ", a[i][j]);       }       System.out.println();    } }