# C Program to Find HCF (GCD) and LCM Using Recursive Function

**Question: ** Write a program in C to find Highest Common Factor (HCF) ( also known as Greatest Common Divisor (GCD)) and Least Common Multiple (LCM) using Recursive Function.

## HCF and LCM Using Recursive Function

```
#include <stdio.h>
long int hcf(long int, long int);
int main()
{
long int number1, number2, gcd, lcm;
printf("Enter two integer numbers:\n");
scanf("%ld%ld", &number1, &number2);
gcd = hcf(number1, number2);
lcm = (number1*number2)/gcd;
printf("HCF of %ld and %ld = %ld\n", number1, number2, gcd);
printf("LCM of %ld and %ld = %ld\n", number1, number2, lcm);
return 0;
}
long int hcf(long int a, long int b) {
if (b == 0)
{
return a;
}
else
{
return hcf(b, a % b);
}
}
```

Output

Enter two integer numbers: 24 36 HCF of 24 and 36 = 12 LCM of 24 and 36 = 72