Check in binary array the number represented by a subarray is odd or even

Given a array such that all its terms is either 0 or 1.You need to tell the number represented by a subarray a[l..r] is odd or even

Examples :

Input : arr = {1, 1, 0, 1}
        l = 1, r = 3
Output : odd
        number represented by arr[l...r] is 
        101 which 5 in decimal form which is 
        odd

Input :  arr = {1, 1, 1, 1}
         l = 0, r = 3
Output : odd

Recommended: Please try your approach on {IDE} first, before moving on to the solution.

The important point to note here is all the odd numbers in binary form have 1 as their rightmost bit and all even numbers have 0 as their rightmost bit.
The reason is simple all other bits other than rightmost bit have even values and sum of even numbers is always even .Now the rightmost bit can have value either 1 or 0 as we know even + odd = odd so when right most bit is 1 the number is odd and when it is 0 the number is even.
So to solve this problem we have to just check if a[r] is 0 or 1 and accordingly print odd or even

C++

// C++ program to find if a subarray 
// is even or odd. 
#include<bits/stdc++.h> 
using namespace std; 
  
// prints if subarray is even or odd 
void checkEVENodd (int arr[], int n, int l, int r) 
{ 
    // if arr[r] = 1 print odd 
    if (arr[r] == 1) 
        cout << "odd" << endl; 
  
    // if arr[r] = 0 print even 
    else
        cout << "even" << endl; 
} 
  
// driver code 
int main() 
{ 
    int arr[] = {1, 1, 0, 1}; 
    int n = sizeof(arr)/sizeof(arr[0]); 
    checkEVENodd (arr, n, 1, 3); 
    return 0; 
} 

Java

// java program to find if a subarray 
// is even or odd. 
import java.io.*; 
  
class GFG  
{ 
    // prints if subarray is even or odd 
    static void checkEVENodd (int arr[], int n, int l, int r) 
    { 
        // if arr[r] = 1 print odd 
        if (arr[r] == 1) 
            System.out.println( "odd") ; 
      
        // if arr[r] = 0 print even 
        else
            System.out.println ( "even") ; 
    } 
  
    // driver code 
    public static void main (String[] args)  
    { 
        int arr[] = {1, 1, 0, 1}; 
        int n = arr.length; 
        checkEVENodd (arr, n, 1, 3); 
          
          
    } 
} 
  
// This article is contributed by vt_m.  

Python3

# Python3 program to find if a  
# subarray is even or odd. 
  
# Prints if subarray is even or odd 
def checkEVENodd (arr, n, l, r): 
  
    # if arr[r] = 1 print odd 
    if (arr[r] == 1): 
        print("odd") 
  
    # if arr[r] = 0 print even 
    else: 
        print("even") 
  
# Driver code 
arr = [1, 1, 0, 1] 
n = len(arr) 
checkEVENodd (arr, n, 1, 3) 
  
# This code is contributed by Anant Agarwal. 

C#

// C# program to find if a subarray 
// is even or odd. 
using System; 
   
class GFG { 
      
    // prints if subarray is even or odd 
    static void checkEVENodd (int []arr,  
                     int n, int l, int r) 
    { 
          
        // if arr[r] = 1 print odd 
        if (arr[r] == 1) 
            Console.WriteLine( "odd") ; 
       
        // if arr[r] = 0 print even 
        else
            Console.WriteLine( "even") ; 
    } 
   
    // driver code 
    public static void Main()  
    { 
          
        int []arr = {1, 1, 0, 1}; 
        int n = arr.Length; 
          
        checkEVENodd (arr, n, 1, 3); 
    } 
} 
   
// This article is contributed by Anant Agarwal. 

PHP

<?php 
// PHP program to find if a subarray 
// is even or odd. 
  
// prints if subarray is even or odd 
function checkEVENodd ($arr, $n, $l, $r) 
{ 
    // if arr[r] = 1 print odd 
    if ($arr[$r] == 1) 
        echo "odd", "\n"; 
  
    // if arr[r] = 0 print even 
    else
        echo "even", "\n"; 
} 
  
// Driver code 
$arr = array(1, 1, 0, 1); 
$n = sizeof($arr); 
checkEVENodd ($arr, $n, 1, 3); 
  
// This code is Contributed by Ajit 
?> 

Output :

odd

This article is contributed by Ayush Jha. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.

My Personal Notes

Recommended: Please try your approach on {IDE} first, before moving on to the solution.

C++

Java

Python3

C#

PHP

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