Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
JavaScript function to take a number n and generate an array with first n prime numbers
We are required to write a JavaScript function that takes in a number n and returns an array that contains first n prime numbers. We know that prime numbers are those numbers that are only divisible by 1 and themselves like 2, 3, 19, 37, 73 etc.
We will first write a function that checks whether a given number is prime or not and then run a loop to generate n prime numbers. The code to check for prime numbers −
const isPrime = (n) => {
for(let i = 2; i <= n/2; i++){
if(n % i === 0){
return false;
}
};
return true;
};And the full generating code will be −
Example
const isPrime = (n) => {
for(let i = 2; i <= n/2; i++){
if(n % i === 0){
return false;
}
};
return true;
};
const generatePrime = num => {
const arr = [];
let i = 2;
while(arr.length < num){
if(isPrime(i)){
arr.push(i);
};
i = i === 2 ? i+1 : i+2;
};
return arr;
};
console.log(generatePrime(6));
console.log(generatePrime(16));
console.log(generatePrime(36));Output
The output in the console will be −
[ 2, 3, 5, 7, 11, 13 ] [ 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53 ] [ 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151 ]
Updated on: 28-Aug-2020
1K+ Views
Advertisements