So for my assignment, I have to write a program that asks the user for an integer input and then print out that number's prime factorization. This is what I have:
import java.util.Scanner;
public class PrimeFactor {
public static void main(String[] args) {
System.out.print("Enter a positive number: ");
Scanner scanner = new Scanner (System.in);
int number = scanner.nextInt();
int count;
for (int i = 2; i<=(number); i++) {
count = 0;
while (number % i == 0) {
number /= i;
count++;
if (count == 0) {
continue;
}
}
System.out.println(i+ "**" + count);
}
}
}
The problem I have right now is that whenever I run it with, like, the number 15453, I get a list of every factor from 1 to 100 and its exponent when I only want the prime factors, and I'm stuck as to how to proceed.
You are almost there! Move the if-continue
block outside the for
loop. Otherwise, it "continues" the inner-most loop, rather than the one you intended.
while (number % i == 0) {
number /= i;
count++;
}
if (count == 0) {
continue;
}
System.out.println(i+ "**" + count);
Alternatively, you could enclose the System.out.println
call in if (count != 0)
, because it's the only statement following the continue
:
while (number % i == 0) {
number /= i;
count++;
}
if (count != 0) {
System.out.println(i+ "**" + count);
}
Your program on ideone: link.