#include <stdio.h>
#include <math.h>

/* Use: `grep xxx AlienHz.c` where xxx is the second word on next line:
gcc -Wall -W -pedantic -O3 -ffast-math -lm -o AlienHz AlienHz.c
 */
int main(void)
{
	int Index,d;
	
	double base, exp;
	const double Bases[] = 
	{
		1,
		3.141592653589793238462643383279502884197169399375105820974944592,
		2.718281828459045235360287471352662497757247093699959574966967628,
		1.41421356237309504880168872420969807856967187537694807317667973,
		0
	};
	
	printf(
		"The most probable messaging frequencies between 800 MHz .. 3 GHz\n"
		"\n"
		"Based on the following base numbers, multiplicated with\n"
		"several possible number system bases raised to 4..30 power:\n");
		
	for(Index=0; Bases[Index] != 0; Index++)
		printf("%.15f ", Bases[Index]);
		
	printf("\n(One, pi, e and sqrt(2))\n\n");	
	
	for(d=0,base=2; base<32; base++)
		for(exp=4; exp<30; exp++)
		{
			double res, mul=pow(base, exp);
			
			for(Index=0; (res=Bases[Index]) != 0; Index++)
			{
				res *= mul;
				if(res >= 800E6 && res <= 3E9)	/* 800 MHz .. 3 GHz */
				{
					if(d++%4==3)printf("\n");
					printf("%16.10f MHz", res / 1E6);
				}
			}
		}
		
	printf("\n(%d)\n", d);
	
	return 0;
}