for, for of, for in

for

let str = '';

for (let i = 0; i < 9; i++) {
  str = str + i;
}

console.log(str);
// Expected output: "012345678"

 

for of

const array1 = ['a', 'b', 'c'];

for (const element of array1) {
  console.log(element);
}

// Expected output: "a"
// Expected output: "b"
// Expected output: "c"

 

for in

const object = { a: 1, b: 2, c: 3 };

for (const property in object) {
  console.log(`${property}: ${object[property]}`);
}

// Expected output:
// "a: 1"
// "b: 2"
// "c: 3"