Zig-zag matrix - Rosetta Code

Zig-zag matrix - Rosetta Code
Produce a zig-zag array. A zig-zag array is a square arrangement of the first N² integers, where the numbers increase sequentially as you zig-zag along the anti-diagonals of the array.

public static int[][] Zig_Zag(final int size)
{
 int[][] data = new int[size][size];
 int i = 1;
 int j = 1;
 for (int element = 0; element < size * size; element++)
 {
  data[i - 1][j - 1] = element;
  if ((i + j) % 2 == 0)
  {
   // Even stripes
   if (j < size)
    j++;
   else
    i+= 2;
   if (i > 1)
    i--;
  }
  else
  {
   // Odd stripes
   if (i < size)
    i++;
   else
    j+= 2;
   if (j > 1)
    j--;
  }
 }
 return data;
}

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