Java > Array-3 > squareUp (CodingBat Solution)

Problem:

Given n>=0, create an array length n*n with the following pattern, shown here for n=3 : {0, 0, 1, 0, 2, 1, 3, 2, 1} (spaces added to show the 3 groups).

squareUp(3) → {0, 0, 1, 0, 2, 1, 3, 2, 1}
squareUp(2) → {0, 1, 2, 1}
squareUp(4) → {0, 0, 0, 1, 0, 0, 2, 1, 0, 3, 2, 1, 4, 3, 2, 1}

Solution:

public int[] squareUp(int n) {
  int[] result = new int[n * n];
  int x = n-1, pass = 1, index = 0;
  if(n == 0) { return result; }
  for(int i = n-1; i < result.length; i+=n) {
     index = i;
     for(int k = 1; k <= pass; k++) {
       if(k == 0) { break; }
       result[index] = k;
       index--;
     }
     pass++;
  }
  return result;
}