calculate prime number js code example
Example 1: javascript find a prime number
// This seems to be the most common and comprehensive means
// of implementing a 'is a number a prime function' in javascript
// if you would like t0 learn more complex , but efficient algorithms.
// Visit the link below
// https://stackoverflow.com/questions/11966520/how-to-find-prime-numbers-between-0-100
function isPrime(num) {
if(num < 2) return false;
for (let k = 2; k < num; k++){
if( num % k == 0){
return false;
}
}
return true;
}
Example 2: Prime number function Js
// program to check if a number is prime or not
function isPrime(){
// take input from the user
const number = parseInt(prompt("Enter a positive number: "));
let isPrime = true;
// check if number is equal to 1
if (number === 1) {
console.log("1 is neither prime nor composite number.");
}
// check if number is greater than 1
else if (number > 1) {
// looping through 2 to number-1
for (let i = 2; i < number; i++) {
if (number % i == 0) {
isPrime = false;
break;
}
}
if (isPrime) {
console.log(`${number} is a prime number`);
} else {
console.log(`${number} is a not prime number`);
}
}
// check if number is less than 1
else {
console.log("The number is not a prime number.");
}
}