Prime Factor any of the prime numbers that can be multiplied to give the original number.
Example: The prime factors of 15 are 3 and 5 (because 3×5=15, and 3 and 5 are prime numbers).
using System; namespace prime { public class ReturnPrimeFactors { // Entry Point public static void Main() { Console.WriteLine("Enter number: "); int userInput = Convert.ToInt32(Console.ReadLine()); PrimeFactors(userInput); Console.Read(); } public static void PrimeFactors(int n) { while (n % 2 == 0) { Console.Write(2 + " "); n /= 2; } for (int i = 3; i <= Math.Sqrt(n); i += 2) { while (n % i == 0) { Console.Write(i + " "); n /= i; } } if (n > 2) // output factors Console.Write(n); } } }
Output