I can't find mistake in my code...what should I do?

package com.codegym.task.task04.task0428; /* Positive number */ import java.io.*; public class Solution { public static void main(String[] args) throws Exception { //write your code here BufferedReader bf=new BufferedReader(new InputStreamReader(System.in)); String x=bf.readLine(); String y=bf.readLine(); String z=bf.readLine(); int a=Integer.parseInt(x); int b=Integer.parseInt(y); int c=Integer.parseInt(z); int num=0; if (a>0) num++; else if(b>0)num++; else if(c>0)num++; System.out.println(num) ; } }