JSFiddle - React, Tailwind, and code Playground
JavaScript
A = [1, 2, 3, 4,5,6,7,8,9];
B = [1, 3, 4,3,8,5];
diff = A.filter(function(x) { return B.indexOf(x) < 0 })
document.body.appendChild(document.createTextNode(diff));
A = [1, 2, 3, 4,5,6,7,8,9];
B = [1, 3, 4,3,8,5];
diff = A.filter(function(x) { return B.indexOf(x) < 0 })
document.body.appendChild(document.createTextNode(diff));