# C Program to check Prime Number

First of all a prime number is a positive integer that is divisible only by 1 and itself. For example: 2. 3, 5, 7, 11, 13, 17 Implementation Using C: #include<stdio.h>

int main()

{

int i, n, flag = 1;

printf("Enter a positive integer: ");

scanf("%d", &n);

for(i = 2; i <= n/2; i++)

{

if(n % i == 0)

{

flag = 0;

break;

}

}

if(n == 1)

printf("1 is neither prime nor composite");

else{

if(flag == 1) }

printf("%d is a prime number", n);

else

printf("%d is not a prime number", n);

}

return 0;

} Output:

Enter a positive integer: 19

19 is a prime number Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above. Follow Programmers Door for more. #programming #blog #placement_prep