Loops

While Loop

while (condition) {
  // code block to be executed
}

let i = 0;
while (i < 5) {
  console.log(i);
  i++;
}

Reverse Loop

const fruits = ["apple", "orange", "banana"];

for (let i = fruits.length - 1; i >= 0; i--) {
  console.log(`${i}. ${fruits[i]}`);
}

// => 2. banana
// => 1. orange
// => 0. apple

Do…While Statement

x = 0;
i = 0;

do {
  x = x + i;
  console.log(x);
  i++;
} while (i < 5);
// => 0 1 3 6 10

For Loop

for (let i = 0; i < 4; i += 1) {
  console.log(i);
}

// => 0, 1, 2, 3

Looping Through Arrays

for (let i = 0; i < array.length; i++) {
  console.log(array[i]);
}

// => Every item in the array

Break

for (let i = 0; i < 99; i += 1) {
  if (i > 5) {
    break;
  }
  console.log(i);
}
// => 0 1 2 3 4 5

Continue

for (i = 0; i < 10; i++) {
  if (i === 3) {
    continue;
  }
  text += "The number is " + i + "<br>";
}

Nested

for (let i = 0; i < 2; i += 1) {
  for (let j = 0; j < 3; j += 1) {
    console.log(`${i}-${j}`);
  }
}

for...in loop

const fruits = ["apple", "orange", "banana"];

for (let index in fruits) {
  console.log(index);
}
// => 0
// => 1
// => 2

for...of loop

const fruits = ["apple", "orange", "banana"];

for (let fruit of fruits) {
  console.log(fruit);
}
// => apple
// => orange
// => banana

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