Light Bulbs

Problem

Given n light bulbs, write two methods.

isOn(i) to determine if a light bulb is on
toggle(start, end) to toggle all the light bulbs in the range

One caveat, write toggle so that it is less than O(n) complexity

Solution

public class LightBulbs {

 int lights=0b11010;
 boolean isOn(int i) {
  int temp = lights>>i & 1;
  if(temp == 1) return true;
  return false;
 }
 
 int toggle(int start, int end)
 {
  int temp = 1<<(end-start+1);
  temp = temp-1;
  temp <<= start;
  lights = lights^temp;
  
  return lights;
 }
 
 String convertToBinary(int i){
  return Integer.toString(i, 2);
 }
 
 public static void main(String[] args) {
   
  LightBulbs ob = new LightBulbs();
  System.out.println(ob.isOn(0)); 
  
  int newLight = ob.toggle(1,3);
  System.out.println(ob.convertToBinary(newLight));
 }
}