UVA - 583 - Prime Factors

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.LinkedList;

public class Main {

    public static void main(String[] args) throws IOException {
        InputStreamReader isr = new InputStreamReader(System.in);
        BufferedReader br = new BufferedReader(isr);
        StringBuffer sb = new StringBuffer("");
        String m = "";
        while(true) {
           int x=Integer.parseInt(br.readLine());
           if(x==0)
               break;
           int[] arr=primeFactors(x);
           sb.append(x).append(" =");
           for(int i=0;i<arr.length;i++){
               if(i>0)
                    sb.append(" x");
               sb.append(" ").append(arr[i]);
           }
            sb.append("\n");
        }
        System.out.print(sb);
    }
   
    static int[] primeFactors(int x){
        LinkedList<Integer> list=new LinkedList<Integer>();
        if(x<0){
            list.add(-1);
        }
        int temp=Math.abs(x);
        boolean notprime=false,entered=false;
        while(temp>1 &&!notprime){
            entered=false;
            for(int i=2;i<Math.sqrt(temp)+1;i++){
                if(temp%i==0){
                    list.add(i);
                    temp/=i;
                    notprime=false;
                    entered=true;
                    break;
                }
            }
            if(!entered)
                 notprime=true;
        }
        if(notprime){
                list.add(temp);
            }
        int[] arr=new int[list.size()];
        for(int i=0;i<arr.length;i++){
            arr[i]=list.get(i);
        }
        return arr;
    }
}