recursion

Hi!

Please take a look at the code and tell me, why there is an infinite loop in recursive function?

Code:

# include <stdio.h>



void pIt (float X1);
void pRe (float X1, int I);


int main ()
{
	float X1 = 100;
	int I = 100;



	printf ("Iterative function\n");
	pIt (X1);
	printf ("\n\nRecursive function\n");
	pRe (X1, I);
	getchar ();
	return 0;
}
void pIt (float X1)
{
	int I = 100;



	while ( (I > 0) && (X1 > 1) )
	{
		X1 = (float) (X1 * 0.5);
		I  = I - 1;
	}
	printf ("X1 = %f", X1);
}
void pRe (float X1, int I)
{
	while ( (I > 0) && (X1 > 1) )
	{
		pRe ((float) (X1*0.5), I-1);
		printf ("\n1. X1 = %f", X1); // X1 here is not under 1 - WHY ??
		printf ("\nI = %d", I);
		getchar ();
	}
	printf ("2. X1 = %f", X1); // X1 is here under 1
}

Thanks.