Modulo operator in TypeScript

TL ; DR:

• The modulo operator (%) calculates the remainder of dividing two values:

  console.log(10 % 2); // Output: 0
  console.log(15 % 4); // Output: 3
  console.log(20 % 3); // Output: 2
  

  
  

• It can also be used with variables:

  let a = 2;
  let b = 4;
  
  console.log(b % a); // Output: 0
  console.log(11 % b); // Output: 3
  

Full lesson:

Remember how we first learn about the division of two integer numbers in primary school?

The quotient is the number of times a division is completed fully, while the remainder is the amount left that doesn't entirely go into the divisor.

Here are some examples:

10 / 2 = quotient 5, remainder 0
15 / 4 = quotient 3, remainder 3
20 / 3 = quotient 6, remainder 2

The modulo operator:

The modulo operator (%) calculates the remainder of dividing two values:

console.log(10 % 2); // Output: 0
console.log(15 % 4); // Output: 3

It can also be used with variables:

let a = 2;
let b = 4;

console.log(b % a); // Output: 0

console.log(11 % b); // Output: 3

Math.floor() function

The Math.floor() function returns the largest integer less than or equal to a given number:

console.log(Math.floor(3.9)); // Output: 3
console.log(Math.floor(5.2)); // Output: 5
console.log(Math.floor(7)); // Output: 7

We can use this function if we want to compute the integral part of some division (quotient):

// Declare 2 variables and initialize them:
let a = 2;
let b = 3;

let c = Math.floor(b / a);
console.log(c); // Output: 1

Quotient and remainder

In programming, we combine both these concepts to get the quotient and remainder of some division:

// Let's divide 26 by 3:
let quotient = Math.floor(26 / 3);
let remainder = 26 % 3;

console.log(quotient); // Output: 8
console.log(remainder); // Output: 2

Assignment
Follow the Coding Tutorial and let's practice with quotient and remainder!

Hint
Look at the examples above if you get stuck.