C Program For Prime Factors using Functions.

C Program For Prime Factors using Functions.
A positive integer is entered through the keyboard.
Write a function to obtain the prime factors of this number.
For example, prime factors of 24 are 2, 2, 2 and 3, whereas prime factors of 35 are 5 and 7.

#include
main()
{

int number;
int prime(int number);

int primefactor(int number);


printf("Enter the number whose prime factors are to be calculated:");

scanf ("%d", &number);

primefactor(number);

}

//The following function detects a Prime number.

prime(int num)
{
int i, ifprime;


for (i=2; i<=num-1; i++)

{
if (num%i==0)
{

ifprime=0;
}
else
ifprime=1;

}
return (ifprime);
}


//The following function prints the prime factors of a number.

primefactor(int num)
{
int factor,ifprime;
for (factor=2; factor<=num;)

{
prime(factor); //so that the factors are only prime and nothing else.
if (ifprime)

{
if (num%factor==0) //diving by all the prime numbers less than the number itself.
{

printf("%d ", factor);
num=num/factor;

continue;
}
else
{
factor++;//this cannot be made a part of the for loop

}
}
}
return 0;
}