In this article, you’ll learn how to check oddeven number in C++ programming without giving input from the keyboard or giving input from the keyboard.
Look at in the above diagram:
To check oddeven number we generally use modulo operator, we divide the given number with modulo operator and if get remainder == 0 then we say that the given number is even, otherwise, we say that the given number is odd.
Example 1: write a program in C++ language to check a number is odd even without giving input from keyboard
#include<iostream>
using namespace std; int main() { int num=52 ; if(num%2==0) cout<<num<<” is an Even number”<<endl; else cout<<num<<” is an Odd number”; return 0; } 
The Output of this program:
52 is an Even number 
Example 2: write a program in C++ language to check a number is oddeven, an input is given by user from the keyboard.
Solution:
#include<iostream>
using namespace std; int main() { int num ; cout<<“Enter an integer number: “; cin>>num; if(num%2==0) cout<<num<<” is an Even number”<<endl; else cout<<num<<” is an Odd number”; return 0; } 
The Output of this program:
Enter an integer number: 36 36 is an Even number 
Example 3: Write a C++ Program to check oddeven number using the ternary operator, without input from the keyboard.
Solution:
#include<iostream>
using namespace std; int main() { int num=78; (num%2==0) ? cout<<num<<” is an Even number” :cout<<num<<” is an Odd number”; return 0; } 
The output of this program:
78 is an Even number 
Note: Ternary operator must write in a single statement;
The syntax of the ternary operator or conditional operator:
(condition) ? statement 1: statement 2; 
Note: if the condition is true then statement 1 is executed and if the condition is false statement 2 is executed.
Example 4: Write a C++ Program to check oddeven number using ternary operator, with input from the keyboard
Solution:
#include<iostream>
using namespace std; int main() { int num; cout<<“Enter an integer number: “; cin>>num; (num%2==0) ? cout<<num<<” is an Even number” :cout<<num<<” is an Odd number”; return 0; }

The output of this program:
Enter an integer number: 57 57 is an Odd number 
Example 4: Write a C++ Program to check oddeven number without using module (%) operator, without input from the keyboard.
#include<iostream>
using namespace std; int main() { int num=69 ; if(num &1) cout<<num<<” is an Odd number”<<endl; else cout<<num<<” is an Even number”; return 0; } 
The output of this program:
69 is an Odd number 
Note: In the above program we use & (bitwise AND) operator, this operator works on the binary number. When we transform an even number into binary form then its last bit always 0 and binary of number 1 in the last bit is 1 then we get result 0 (false). since 0*1=0 it means else part is executed, on the other hand, if we transform an odd number into binary form then its last digit always 1 and it gives true and if part is executed.
Example 5: Write a C++ Program to check oddeven number without using module (%) operator, with input from the keyboard.
#include <stdio.h>
#include <conio.h> int main() { int num; printf(“Enter a integer number: “); scanf(“%d”,&num); if (num & 1) printf(“%d is an Odd number “,num); else printf(“%d is an Even number”,num); getch(); } 
The Output of this program:
Enter an integer number: 96 96 is an Even number 