Program to find Prime Factors using Functions.

Program to find Prime Factors using Functions.

#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 is the function that 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; 
}