TCS Coding Practice Question | Check Odd or Even

Given a number, the task is to check if this number is Odd or Even using Command Line Arguments. A number is called even if the number is divisible by 2 and is called odd if it is not divisible by 2.

Examples:

Input: 123
Output: No

Input: 588
Output: Yes

Approach:

• Since the number is entered as Command line Argument, there is no need for a dedicated input line
• Extract the input number from the command line argument
• This extracted number will be in string type.
• Convert this number into integer type and store it in a variable, say num
• Check if this number is completely divided by 2
• If completely divisible, the number is Even
• If not completely divisible, the number is Odd

Program:

C++

#include <iostream>
#include <cstdlib> // For atoi function

// Function to check if a number is even or odd
int isEvenOrOdd(int num) {
    return (num % 2);
}

// Driver code
int main(int argc, char* argv[]) {
    int num, res = 0;

    // Check if the length of args array is 1
    if (argc == 1)
        std::cout << "No command line arguments found." << std::endl;
    else {
        // Convert the command line argument to an integer
        num = std::atoi(argv[1]);
        
        // Check if it is even or odd
        res = isEvenOrOdd(num);

        // Check if res is 0 or 1
        if (res == 0)
            std::cout << "Even" << std::endl;
        else
            std::cout << "Odd" << std::endl;
    }
    return 0;
}

// code contributed by Oprix

C

// C program to check
// if a number is even or odd
// using command line arguments

#include <stdio.h>
#include <stdlib.h> /* atoi */

// Function to the check Even or Odd
int isEvenOrOdd(int num)
{
    return (num % 2);
}

// Driver code
int main(int argc, char* argv[])
{

    int num, res = 0;

    // Check if the length of args array is 1
    if (argc == 1)
        printf("No command line arguments found.\n");

    else {

        // Get the command line argument and
        // Convert it from string type to integer type
        // using function "atoi( argument)"
        num = atoi(argv[1]);

        // Check if it is even or odd
        res = isEvenOrOdd(num);

        // Check if res is 0 or 1
        if (res == 0)
            // Print Even
            printf("Even\n");
        else
            // Print Odd
            printf("Odd\n");
    }
    return 0;
}

Java

// Java program to check
// if a number is even or odd
// using command line arguments

class GFG {

    // Function to the check Even or Odd
    public static int isEvenOrOdd(int num)
    {
        return (num % 2);
    }

    // Driver code
    public static void main(String[] args)
    {

        // Check if length of args array is
        // greater than 0
        if (args.length > 0) {

            // Get the command line argument and
            // Convert it from string type to integer type
            int num = Integer.parseInt(args[0]);

            // Get the command line argument
            // and check if it is even or odd
            int res = isEvenOrOdd(num);

            // Check if res is 0 or 1
            if (res == 0)
                // Print Even
                System.out.println("Even\n");
            else
                // Print Odd
                System.out.println("Odd\n");
        }
        else
            System.out.println("No command line "
                               + "arguments found.");
    }
}

Python

import sys

# Function to check if a number is even or odd
def is_even_or_odd(num):
    return num % 2

# Driver code
if len(sys.argv) == 1:
    print("No command line arguments found.")
else:
    num = int(sys.argv[1])
    res = is_even_or_odd(num)
    if res == 0:
        print("Even")
    else:
        print("Odd")
        
# contributed by oprix

JavaScript

// Function to check if a number is even or odd
function isEvenOrOdd(num) {
    return num % 2;
}

// Driver code
if (process.argv.length === 2) {
    console.log("No command line arguments found.");
} else {
    const num = parseInt(process.argv[2]);
    const res = isEvenOrOdd(num);
    if (res === 0) {
        console.log("Even");
    } else {
        console.log("Odd");
    }
}

// code contributed by Oprix

Output:

• In C:
• In Java:

Time Complexity: O(1)
Auxiliary Space: O(1)