In this article, you’ll learn how to check odd-even number in C programming without giving input from the keyboard or giving input from the keyboard.

Look at in the above diagram:

### To check odd-even 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 <stdio.h>
#include <conio.h> int main() { int num=36; if (num%2==0) printf(“%d is an Even number “,num); else printf(“%d is an Odd number”,num); getch(); } |

The Output of this program:
36 is an Even number |

Example 2: write a program in C language to check a number is odd-even, the input is given by the user from the keyboard.

Solution:

#include <stdio.h>
#include <conio.h> int main() { int num; printf(“Enter an integer number: “); scanf(“%d”,&num); if (num%2==0) printf(“%d is an Even number “,num); else printf(“%d is an Odd number”,num); getch(); } |

The Output of this program:
Enter an integer number: 95 95 is an Odd number |

Example 3: Write a C Program to check odd-even number using the ternary operator, without input from the keyboard.

Solution:

#include <stdio.h>
#include <conio.h> int main() { int num=89; (num%2==0)?printf(“%d is an Even number “,num): printf(“%d is an Odd number”,num); getch(); } |

The output of this program:
89 is an Odd number |

Note: Ternary operator must write in a single statement;

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 odd-even number using ternary operator, with input from the keyboard

Solution:

#include <stdio.h>
#include <conio.h> int main() { int num; printf(“Enter an integer number:”); scanf(“%d”,&num); (num%2==0)?printf(“%d is an Even number “,num):printf(“%d is an Odd number”,num); getch(); } |

The output of this program:
Enter an integer number:93 93 is an Odd number |

Example 4: Write a C Program to check odd-even number without using module (%) operator, without input from the keyboard.

#include <stdio.h>
#include <conio.h> int main() { int num=66; if (num & 1) printf(“%d is an Odd number “,num); else printf(“%d is an Even number”,num); getch(); } |

The output of this program:
66 is an Even 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 odd-even number without using module (%) operator, with input from the keyboard.

#include <stdio.h>
#include <conio.h> int main() { int num; printf(“Enter an integer number: “); scanf(“%d”,&num); if (num & 1) printf(“%d is an Odd number “,num); else printf(“%d is an Even number”,num); getch(); } |

Enter an integer number: 46
46 is an Even number |