The residual is the quantity “left over” after executing a calculation in mathematics. The residual is the integer that remains after dividing one integer by another to obtain an integer quotient in arithmetic. Remainder concept is very important to execute odd or even program in c using if else

A whole number that may be split into two equal whole numbers by two. Even numbers are zero, two, four, six, and eight.

Whole numbers that cannot be split perfectly into pairs are known as odd numbers. Odd numbers have a residual of one when divided by two.

```
//odd or even program in c using if else
#include <stdio.h>
void main()
{
int value, rem;
printf("Enter an int ");
scanf("%d", &value);
rem = value % 2;
if (rem == 0)
printf("%d is an even int\n", value);
else
printf("%d is an odd int\n", value);
}
```

Output:

Enter an int 45

45 is an odd int