How to subtract one array from another, element-wise, in javascript

Question

If i have an array A = [1, 4, 3, 2] and B = [0, 2, 1, 2] I want to return a new array (A - B) with values [1, 2, 2, 0]. What is the most efficient approach to do this in javascript?

Answer 1

const A = [1, 4, 3, 2]  const B = [0, 2, 1, 2]  console.log(A.filter(n => !B.includes(n)))

Answer 2

Use map method The map method takes three parameters in it's callback function like below

currentValue, index, array 

var a = [1, 4, 3, 2],    b = [0, 2, 1, 2]    var x = a.map(function(item, index) {    // In this case item correspond to currentValue of array a,     // using index to get value from array b    return item - b[index];  })  console.log(x);