javascript get elements that exist in two arrays
function getArraysIntersection(a1,a2){ return a1.filter(function(n) { return a2.indexOf(n) !== -1;}); } var colors1 = ["red","blue","green"]; var colors2 = ["red","yellow","blue"]; var intersectingColors=getArraysIntersection(colors1, colors2); //["red", "blue"]