How do you loop through an array?

Question

Accepted Answer

forEach: available on array instance for for in for of map: available on array instance reduce: available on array instance const array1 = ["a", "b", "c"];

array1.forEach((element) => console.log(element));

// Expected output: "a"
// Expected output: "b"
// Expected output: "c" let str = "";

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

console.log(str);
// Expected output: "012345678" for (variable in object)
  statement

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

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

// Expected output: "a"
// Expected output: "b"
// Expected output: "c"
 const array1 = [1, 4, 9, 16];

// Pass a function to map
const map1 = array1.map((x) => x * 2);

console.log(map1);
// Expected output: Array [2, 8, 18, 32]

const numbers = [1, 4, 9];
const roots = numbers.map((num) => Math.sqrt(num));

// roots is now     [1, 2, 3]
// numbers is still [1, 4, 9] const array1 = [1, 2, 3, 4];
  
  // 0 + 1 + 2 + 3 + 4
  const initialValue = 0;
  const sumWithInitial = array1.reduce(
    (accumulator, currentValue) => accumulator + currentValue,
    initialValue,
  );
  
  console.log(sumWithInitial);
  // Expected output: 10

How do you loop through an array?

There are many ways in which we can loop through an array:

How do you loop through an array?

There are many ways in which we can loop through an array:

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