/* This is notation for comments in C and C++.  I have two programs in
this file, the first for summing 1/n and the second for summing x^n. */

#include <math.h>		/* Reference some standard C++ libraries. */
#include <stdlib.h>             
#include <iostream.h>           

main ()
{
	int i;
	double sum=0;          /* Initialize the sum to zero. */
	
	for(i=1; i<1000; i++) {       /* Take 1000 terms. */
		sum += 1./i;          /* Add 1/i to the running total. */
		cout << i <<"		"<<sum<<"\n";   /* Output to screen. */
	}
	   
   	return 0;
} 

/* That's the end of the 1/n summation.  To use that, cut above this line! */

/* Below this is the x^n program.  To use it, cut below this line! */



#include <math.h>
#include <stdlib.h>
#include <iostream.h>

main ()
{
	int i, flag;
	double sum=0, evalpt = 0.9, exactsum, cutoff;
	
	exactsum = 1./(1.-evalpt);	/* geometric series formula */
	cutoff = 0.01*exactsum;		/* get within 1 percent */
	for(i=0; i<1000; i++) {
	    sum += pow(evalpt, i);
	    if (exactsum - sum < cutoff) {
		cout << "i=" <<i<<"\n";
		cout << "exactsum="<<exactsum<<"\n";
		i = 1000;		/* jump out of loop if close enough */
	    }
	}
	   
   	return 0;
}