How to execute integer division and retrieve the remainder in JavaScript?

Other Questions JavaScript
1

In JavaScript, what is the method to find the following:

  1. The exact count of how many times one integer fits completely into another?
  2. The leftover value after that division?
2

In JavaScript, if you’re looking to perform integer division and also capture the remainder, you can achieve this using basic operators. There isn’t a single built-in function for integer division, but you can accomplish these tasks using the combination of the floor division and modulus operators.

To find the count of how many times one integer fits into another (quotient), you can use:

const dividend = 29;
const divisor = 6;
const quotient = Math.floor(dividend / divisor);
console.log(quotient); // Output: 4

Here, we use Math.floor() to round down the result of dividend / divisor to the nearest whole number, which effectively gives you the integer division.

To find the remainder after the division, the modulus operator % can be used:

const remainder = dividend % divisor;
console.log(remainder); // Output: 5

In this example, the % operator gives you the leftover after dividing 29 by 6.

Together, these expressions allow you to perform integer division and retrieve both the quotient and the remainder efficiently. This approach ensures clarity and simplicity, which is beneficial even for those who are new to JavaScript.

3

For an alternative approach, use ES6 to calculate both the quotient and remainder in one go:

const [dividend, divisor] = [29, 6];
const quotient = ~~(dividend / divisor); // Output: 4
const remainder = dividend % divisor;    // Output: 5

By using the ~~ operator, you perform a bitwise NOT twice, effectively simulating Math.floor() for non-negative numbers. This method is concise and works well for integers.

4

Another approach for performing integer division and finding the remainder in JavaScript is to use the parseInt() function, which can handle the conversion to an integer division effectively.

const dividend = 29;
const divisor = 6;
const quotient = parseInt(dividend / divisor);
console.log(quotient); // Output: 4

The parseInt() function converts the floating-point result of the division into an integer, effectively providing the quotient without the need for additional logic like Math.floor() or bitwise operations.

For obtaining the remainder, you can still utilize the modulus operator %, which remains the most direct way to achieve this:

const remainder = dividend % divisor;
console.log(remainder); // Output: 5

This method of using parseInt() might be seen as more intuitive for some developers, especially those who prefer to avoid bitwise operations, and it aligns with JavaScript’s built-in capabilities for handling numerical transformations. This approach is practical, especially when working in environments where concise and straightforward code is preferred.

5

To accomplish integer division and find the remainder in JavaScript while keeping your code efficient and clear, consider implementing a custom function to encapsulate this logic. This approach not only improves readability but also reusability.

Here is how you can implement it:

function integerDivisionAndRemainder(dividend, divisor) {
  const quotient = (dividend / divisor) | 0; // Bitwise OR with 0 eliminates the decimal
  const remainder = dividend % divisor;
  return { quotient, remainder };
}

const { quotient, remainder } = integerDivisionAndRemainder(29, 6);
console.log(`Quotient: ${quotient}, Remainder: ${remainder}`); // Output: Quotient: 4, Remainder: 5

Explanation:

  • The expression (dividend / divisor) | 0 uses the bitwise OR operator to truncate the decimal, effectively performing integer division.
  • You then compute the remainder using the % modulus operator.

This method streamlines the process into a single reusable function, enhancing maintainability and focusing on clarity, which is central to optimizing workflow efficiency.