function diagonalDifference(arr) { // Write your code here const size = arr.length; let sumLeft = 0; let sumRight = 0; for(var i = 0; i < size; i++){ const r = (size -1) - i; sumLeft += arr[i][i]; sumRight += arr[i][r]; } return Math.abs(sumLeft - sumRight); } const a = [ [ 11, 2, 4 ], [ 4, 5, 6 ], [ 10, 8, -12 ] ]; diagonalDifference(a);