Prime number is a number that is greater than 1 and divided by 1 or itself. In other words, prime numbers can't be divided by other numbers than itself or 1. For example 2, 3, 5, 7, 11, 13, 17, 19, 23.... are the prime numbers.
Let's see the prime number program in C#. In this C# program, we will take an input from the user and check whether the number is prime or not.
If you don't know what is prime number please read form this tutorial. Prime Number & Prime Factors
using System;
public class PrimeNumberExample
{
public static void Main(string[] args)
{
int n, i, m=0, flag=0;
Console.Write("Enter the Number to check Prime: ");
n = int.Parse(Console.ReadLine());
m=n/2;
for(i = 2; i <= m; i++)
{
if(n % i == 0)
{
Console.Write("Number is not Prime.");
flag=1;
break;
}
}
if (flag==0)
Console.Write("Number is Prime.");
}
} output 1:
Enter the Number to check Prime: 17
Number is Prime.
Output 2:
Enter the Number to check Prime: 57
Number is not Prime.
First read the algorithm, then study the program code line by line. After that, compare the code with the output and finally go through the explanation. This approach helps learners understand both the logic and the implementation properly.
After understanding this example, try to rewrite the same program without looking at the code. Then change some values or logic and run it again. This helps improve confidence and keeps learners engaged on the page for longer.