A Prime Number can be divided evenly only by 1, or itself.
A Prime Number must be a whole number greater than 1.
3 can only be divided evenly by 1 or 3, so it is a prime number.
But 6 can be divided evenly by 1, 2, 3 and 6 so it is NOT a prime number.
This program accept one Integer from user and checks if it is prime or not. I am using one flag variable and setting that flag to 1 if given number is evenly dividable by any number (except 1 and given number). that’s why my for loop is started with 2 and ended at n/2
Note : There are other efficient ways to write this program. we will discuss them in next posts.