const obj = {
    a: 1,
    b: 2,
    c: 3
};
for (let prop in obj) {
    console.log(prop, obj[prop]);
}
const arr = ["a", "b", "c"];
for (let w = 0; w < arr.length; w++) {
    console.log(w, arr[w]);
}
 
for (el in arr) {
    console.log(el, arr[el]);
}