Program to Find nth Evil Number

An Evil number is a non-negative number that has an even number of 1s in its binary expression.

Example:

               Given Number=3
               3⇒0011(Here Even number of 1s present)
               so, 3 is an Evil Number.
                 
                Given Number=4
               4⇒0100(Here Even number of 1s, not present)
               so, 120 is not an Evil Number.
                                          
Problem statement:-  Program to Find nth Evil Number.

Data requirement:-

   Input Data:- rangenumber

   Output Data:- rangenumber, letest

   Additional Data:- c, num, num1, one_c

Program in C

Here is the source code of the C Program to Find nth Evil Number.

Code:

//Nth Evil Number
#include <stdio.h>
int
main ()
{
  int rangenumber, num = 1, c = 0, letest = 0;
  printf ("Enter the Nth value:");
  scanf ("%d", &rangenumber);
  while (c != rangenumber)
    {
    int num1=num;
    int one_c=0;
   while(num1!=0)
   {
       if(num1%2==1)
       {
           one_c++;
       }
           num1/=2;

   }
   if(one_c%2==0)
   {
          c++;
          letest=num;
    }
      num = num + 1;
    }
  printf ("%dth Evil number is %d", rangenumber, letest);
  return 0;
}

Input/Output:

Enter the Nth value:5
5th Evil number is 10

Program in C++

Here is the source code of the C++ Program to Find nth Evil Number.

Code:

#include <iostream>
using namespace std;
int
main ()
{
  int i, rangenumber, num = 1, c = 0, letest = 0;
  cout<<"Enter the Nth value:";
  cin>>rangenumber;
  while (c != rangenumber)
    {
    int num1=num;
    int one_c=0;
   while(num1!=0)
   {
       if(num1%2==1)
       {
           one_c++;
       }
           num1/=2;

   }
   if(one_c%2==0)
   {
          c++;
          letest=num;
    }
      num = num + 1;
    }
  cout<<rangenumber<<"th Evil number is "<<letest;
  return 0;
}

Input/Output:

Enter the Nth value:7
7th Evil number is 15

Program in Java

  

Here is the source code of the Java Program to Find nth Evil Number.

Code:

import java.util.Scanner;
public class NthEvilNumber {

public static void main(String[] args) {
Scanner cs=new Scanner(System.in);
int  rangenumber, num = 1, c = 0, letest = 0;
  System.out.println("Enter Nth number:");
  rangenumber=cs.nextInt();
           
  while (c != rangenumber)
    {
    int num1=num;
    int one_c=0;
   while(num1!=0)
   {
       if(num1%2==1)
       {
           one_c++;
       }
           num1/=2;

   }
   if(one_c%2==0)
   {
          c++;
          letest=num;
    }
      num = num + 1;
    }
System.out.println(rangenumber+"th Evil number is "+letest);
cs.close();
}
}

Input/Output:

Enter Nth number:
10
10th Evil number is 20

Program in Python
  

Here is the source code of the Program to Find nth Evil Number.

Code:

rangenumber=int(input("Enter a Nth Number:"))
c = 0
letest = 0
num = 1
while c != rangenumber:
    one_c = 0
    num1 = num
    while num1 != 0:
        if num1 % 2 == 1:
            one_c += 1
        num1 //= 2
    if one_c % 2 == 0:
            c+=1
            letest = num

    num = num + 1
print(rangenumber,"th Evil number is ",latest)

Input/Output:

Enter a Nth Number:15
15 th Evil number is  30

More:-

C/C++/Java/Python Practice Question