The below program checks if a number is a prime or a composite number. The C printf statement is used to output the result on the screen.
C program to check prime number
#include <stdio.h> void main() { int x,i; int count = 0; printf("Enter a number:"); scanf("%d",&x); for (i=1; i<=x; i++) { if ((x % i)==0) { count++; } } if (count<3) { printf ("%d is a prime number.", x); } else { printf ("%d is not a prime number.", x); } } |
Output
Enter a number:13 13 is a prime number. |