C Program to Check Prime or Armstrong Number Using User-defined Function
Example to check whether an integer is a prime number or an Armstrong or both by creating two separate functions.
 |
| C Program to Check Prime or Armstrong Number Using User-defined Function |
To understand this example, you should have the knowledge of following C programming topics:
In this program, two user-defined functions
checkPrimeNumber() and checkArmstrongNumber()are created.
The
checkPrimeNumber() returns 1 if the number entered by the user is a prime number. Similarly, checkArmstrongNumber() returns 1 if the number entered by the user is an Armstrong number.Example: Check Prime and Armstrong Number
#include <stdio.h>
#include <math.h>
int checkPrimeNumber(int n);
int checkArmstrongNumber(int n);
int main()
{
int n, flag;
printf("Enter a positive integer: ");
scanf("%d", &n);
// Check prime number
flag = checkPrimeNumber(n);
if (flag == 1)
printf("%d is a prime number.\n", n);
else
printf("%d is not a prime number.\n", n);
// Check Armstrong number
flag = checkArmstrongNumber(n);
if (flag == 1)
printf("%d is an Armstrong number.", n);
else
printf("%d is not an Armstrong number.",n);
return 0;
}
int checkPrimeNumber(int n)
{
int i, flag = 1;
for(i=2; i<=n/2; ++i)
{
// condition for non-prime number
if(n%i == 0)
{
flag = 0;
break;
}
}
return flag;
}
int checkArmstrongNumber(int number)
{
int originalNumber, remainder, result = 0, n = 0, flag;
originalNumber = number;
while (originalNumber != 0)
{
originalNumber /= 10;
++n;
}
originalNumber = number;
while (originalNumber != 0)
{
remainder = originalNumber%10;
result += pow(remainder, n);
originalNumber /= 10;
}
// condition for Armstrong number
if(result == number)
flag = 1;
else
flag = 0;
return flag;
}
Output
Enter a positive integer: 407 407 is not a prime number. 407 is an Armstrong number.
Comments
Post a Comment