Question

In Java, write a program that uses a stack to print the prime factors of a positive integer in descending order.

Answer 1

import java.util.Scanner;
import java.util.Stack;

public class PrimeFactors {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        System.out.print("Enter an integer: ");
        int n = in.nextInt();
        int num = n;
        Stack<Integer> stack = new Stack<>();
        for (int i = 2; i <= n; i++) {
            while (n % i == 0) {
                stack.push(i);
                n /= i;
            }
        }
        System.out.print("Prime factors of " + num + " are:");
        while (!stack.isEmpty()) {
            System.out.print(" " + stack.pop());
        }
        System.out.println();
    }
}