title: How to subtract one array from another, element-wise, in javascript
body: <p>If i have an array <code>A = [1, 4, 3, 2]</code> and <code>B = [0, 2, 1, 2]</code> I want to return a new array (A - B) with values <code>[1, 2, 2, 0]</code>. What is the most efficient approach to do this in javascript?</p>