function diffArray(arr1, arr2) {
return arr1
.concat(arr2)
.filter(item => !arr1.includes(item) || !arr2.includes(item));
}function arrayDiff (a1, a2) {
var a = [], diff = [];
for (var i = 0; i < a1.length; i++) {
a[a1[i]] = true;
}
for (var i = 0; i < a2.length; i++) {
if (a[a2[i]]) {
delete a[a2[i]];
} else {
a[a2[i]] = true;
}
}
for (var k in a) {
diff.push(k);
}
return diff;
}
//usage:
console.log(arrayDiff(['red', 'white','green'], [ 'red','white', 'blue']));//["green", "blue"]var array1 = [1,2,3,4,5,6.25];
var array2 = [9,8,7,6,5,4];
const diffNumber = (arr1, arr2) => arr1.map(function (num, idx) { return num- arr2[idx] });
diffNumber(array2, array1); //[8, 6, 4, 2, 0, -2.25]