Finding prime numbers

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.

Using recursion:

void main()
{
int x;
printf("\nInput an integer\n");
scanf("%d",&x);
prime(x);
}

prime(int x)
{
int a;
for(a=2;a<=x;a++)
{
if(x%a==0)
{
printf("%d ",a);
prime(x/a);
break;
}
}
}


without recursion

void main()
{
int x;
printf("\nInput an integer\n");
scanf("%d",&x);
prime(x);
}

prime(int x)
{
int a;

for(a=2;a<=x;a++)
{
if(x%a==0)
{
printf("%d ",a);
x/=a;
a--;
}
}
}