JavaScript: Compute the greatest common divisor (GCD) of two positive integers

JavaScript Conditional Statement and loops: Exercise-11 with Solution

GCD of Two Numbers

Write a JavaScript program to compute the greatest common divisor (GCD) of two positive integers.

Visual Presentation:

Sample Solution:

JavaScript Code:

// Variables to store the two numbers for which GCD is calculated
var a = 2154; // First number
var b = 458;  // Second number 

var gcd; // Variable to store the Greatest Common Divisor (GCD)

// Iterative loop to find GCD using Euclidean algorithm
while (a != b) {
    // If 'a' is greater than 'b', subtract 'b' from 'a'
    if (a > b) {
        a = a - b;
    } else {
        // If 'b' is greater than 'a', subtract 'a' from 'b'
        b = b - a;
    }
}

// The GCD is stored in 'a'
gcd = a;

// Output the calculated GCD
console.log(gcd); 

Output:

2

Flowchart:

Live Demo:

See the Pen javascript-conditional-statements-and-loops-exercise-11 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript function that computes the greatest common divisor of two numbers using the iterative Euclidean algorithm.
• Write a JavaScript function that calculates the GCD of two numbers recursively while handling negative inputs.
• Write a JavaScript function that finds the GCD of two numbers without using the modulo operator.
• Write a JavaScript function that computes the GCD by using repeated subtraction instead of division.

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