Write a C++ program to check if a number is even or odd.

Algorithm of program to check if a number is even or odd.

1. Start
2. Initialize:
   • number (integer)
3. Input:
   • User inputs 42
   • number = 42
4. Processing:
   • Calculate 42 % 2 which equals 0
   • Since 0 == 0, print “The number 42 is even.”
5. End

Explanation of the Code

1. Include Header Files:
   • #include <iostream>: This header file is required for input and output operations.
2. Using the Standard Namespace:
   • using namespace std;: This line allows us to use standard library names like cout and cin without prefixing them with std::.
3. Main Function:
   • int main() { ... }: This is the entry point of any C++ program. The main function must return an integer.
4. Declare a Variable:
   • int number;: This declares an integer variable to store the user input.
5. Get User Input:
   • cout << "Enter a number: ";: This outputs a prompt asking the user to enter a number.
   • cin >> number;: This reads the user input and stores it in the number variable.
6. Conditional Statement:
   • if (number % 2 == 0) { ... }: This checks if the number is divisible by 2 without a remainder. If true, the number is even.
   • else { ... }: This block executes if the condition in the if statement is false, meaning the number is odd.
7. Output:
   • cout << "The number " << number << " is even." << endl;: This prints the result if the number is even.
   • cout << "The number " << number << " is odd." << endl;: This prints the result if the number is odd.
   • << endl;: This adds a newline character after the output.
8. Return Statement:
   • return 0;: This indicates that the program ended successfully.