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

static float note_frequencies[9][12]={
/* C     C#      D     D#     E       F     F#      G     G#      A     A#      B */
{16.35, 17.32, 18.35, 19.45, 20.60, 21.83, 23.12, 24.50, 25.96, 27.50, 29.14, 30.87},
{32.70, 34.65, 36.71, 38.89, 41.20, 43.65, 46.25, 49.00, 51.91, 55.00, 58.27, 61.74},
{65.41, 69.30, 73.42, 77.78, 82.41, 87.31, 92.50, 98.00, 103.8, 110.0, 116.5, 123.5},
{130.8, 138.6, 146.8, 155.6, 164.8, 174.6, 185.0, 196.0, 207.7, 220.0, 233.1, 246.9},
{261.6, 277.2, 293.7, 311.1, 329.6, 349.2, 370.0, 392.0, 415.3, 440.0, 466.2, 493.9},
{523.3, 554.4, 587.3, 622.3, 659.3, 698.5, 740.0, 784.0, 830.6, 880.0, 932.3, 987.8},
{1047,  1109,  1175,  1245,  1319,  1397,  1480,  1568,  1661,  1760,  1865,  1976},
{2093,  2217,  2349,  2489,  2637,  2794,  2960,  3136,  3322,  3520,  3729,  3951},
{4186,  4435,  4699,  4978,  5274,  5588,  5920,  6272,  6645,  7040,  7459,  7902},
};

static char note_names[12][12]={
	"C","CSHARP","D","DSHARP","E","F","FSHARP","G","GSHARP","A","ASHARP","B",
};

int main(int argc, char **argv) {

	int f,o;
	float value,actual;
	char temp_string[50];

	for(o=3;o<7;o++) {
		for(f=0;f<12;f++) {
			// freq = 1/((20v+17)*1.023e-6)
			// ((20v+17)*1.023e-6)= 1/freq
			// 20v*1.023e-6 + 17*1.023e-6 = 1/freq
			// 20v*1.023e-6 = (1/freq)-17*1.023e-6)
			// v = ((1/freq)-17*1.023e-6)/(20*1.023e-6)

			value=(1.0/(
				(20.0*(1.023e-6)*note_frequencies[o][f])-
					17*1.023e-6
				));

			actual=1.0/((20.0*value+17)*1.023e-6);

//			value = ((1.0/note_frequencies[o][f])-17.0*1.023e-6)/
//					20.0*1.023e-6;

			snprintf(temp_string,50,"NOTE_%s%1d",
				note_names[f],o);

			printf("%-12s = %d\t; %.1f (%.1f)\n",
				temp_string,(int)round(value),
				actual,note_frequencies[o][f]);
		}
	}

	return 0;
}