Pascal’s triangle 2d array – formatting printed output

Here I had modified your code, it prints wonderfully for ROW size till 13, because of the limitation of my console window:

import java.util.*;

public class Pascal {
    public static final int ROW = 12;
    private static int max = 0;

    public static void main(String[] args) {
        int[][] pascal = new int[ROW + 1][];
        pascal[1] = new int[1 + 2];
        pascal[1][1] = 1;
        for (int i = 2; i <= ROW; i++) {
            pascal[i] = new int[i + 2];
            for (int j = 1; j < pascal[i].length - 1; j++) {
                pascal[i][j] = pascal[i - 1][j - 1] + pascal[i - 1][j];
                String str = Integer.toString(pascal[i][j]);
                int len = str.length();
                if (len > max)
                    max = len;
            }
        }

        for (int i = 1; i <= ROW; i++) {
            for (int k = ROW; k > i; k--)
                System.out.format("%-" + max + "s", " ");
            for (int j = 1; j < pascal[i].length - 1; j++)
                System.out.format("%-" + (max + max) + "s", pascal[i][j]);
            System.out.println();
        }
    }
}

Output:

                                 1     
                              1     1     
                           1     2     1     
                        1     3     3     1     
                     1     4     6     4     1     
                  1     5     10    10    5     1     
               1     6     15    20    15    6     1     
            1     7     21    35    35    21    7     1     
         1     8     28    56    70    56    28    8     1     
      1     9     36    84    126   126   84    36    9     1     
   1     10    45    120   210   252   210   120   45    10    1     
1     11    55    165   330   462   462   330   165   55    11    1     

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