Snail

snail-rotate-cc.js

const flipMatrix = matrix => (
  matrix[0].map((column, index) => (
    matrix.map(row => row[index])
  ))
);

const rotateMatrixCounterClockwise = matrix => (
  flipMatrix(matrix).reverse()
);

/*
  [                             [
    [1,2,3],                      [3,6,9],
    [4,5,6],         ->           [2,5,8],
    [7,8,9],                      [1,4,7],
  ];                             ];
*/