how to check if two elements in array equal a number javascript code example

Example 1: check if 2 arrays are equal javascript

const a = [1, 2, 3];
const b = [4, 5, 6];
const c = [1, 2, 3];

function arrayEquals(a, b) {
  return Array.isArray(a) &&
    Array.isArray(b) &&
    a.length === b.length &&
    a.every((val, index) => val === b[index]);
}

arrayEquals(a, b); // false
arrayEquals(a, c); // true

Example 2: javascript get intersection of 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"]