In this Javascript programming example we will cover how to find factorial of a given number. We know that Factorial is a product of number from 1 to given number.
A simple factorial of 0 is always 1.
Syntax of Factorial
Factorial of number x is x (x!)=1*2*.....x;
Let's write a simple Javascript program to find a factorial of a given number.
// Let take input number from the user const num = parseInt(prompt('Enter a number: ')); // check given number os less than 0 if (num < 0) { console.log('Only positive numbers are allowed'); } // check if input = 0 else if (num == 0) { console.log(`The factorial of ${num} is 1.`); } // check if input > 0 else { let fact = 1; for (x = 1; x <= num; x++) { fact *= x; } P a g e | 22 console.log(`The factorial of ${num} is ${fact}.`); } |
Output:
Enter a number : 5
The factorial of 5 is 120
