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🚀 Programming Example

Check whether a given number is prime or not (using for loop)

👁 1,100 Views
💻 Practical Program
📘 Step Learning
A number is said to be prime if it is divisible by 1 and itself. It should not have any other divisors.

💻 Program Code

#include<stdio.h>
void main()
{

int number, i;
int indicator =  0;
printf("Enter a number to check prime or Not: ");
scanf("%d",&number);

for(i = 2; i < number/2; i++)
{
	if(number%i == 0)
	{
	 indicator = 1;
	 break;
	}
}

if(indicator == 1){
	printf(" \n Number %d is not prime. \n", number);
}
else{
	printf(" \n Number %d is prime. \n", number);
}


}
                        

🖥 Program Output

Enter a number to check prime or Not: 13

 Number 13 is prime.
<hr>
Enter a number to check prime or Not: 15

 Number 15 is not prime. 
                            

📘 Explanation

📚 Learning Subject

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🎯 How to learn from this example

First understand the algorithm carefully. Then study the program line-by-line and compare it with the output. Finally, review the explanation section to strengthen your logic and programming understanding.

🔥 Practice suggestion

Rewrite the program without looking at the code. Modify values, conditions or logic and run it again. This helps improve confidence and strengthens coding skills much faster.