/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 4; tab-width: 4 -*- */
/*
 * main.c
 * Copyright (C) DMGualtieri 2011 <gualtieri**at**ieee.org>
 * 
 * triangle is free software: you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * triangle is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License along
 * with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
 /*
 The problem - Can you make a triangle from a stick randomly broken into
 three pieces?  We use the property that the sum of any two sides of a
 triangle must be larger than the remaining side, a principle known as the
 triangle inequality.
*/

// Note - Written more for readability than speed!

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

long int i,j, trials, iterations;
int t_flag,triangle;
float point1,point2,side1,side2,side3, percentage;
FILE *outdata;

//generates a psuedo-random float between 0.0 and 0.999...
float randfloat()
{
    return (((float)rand()/RAND_MAX));
} 

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

if (argc<2)
{
printf("Usage: triangle number_of_trials number_of_iterations\n");
exit(1);
}

//Seed random number generator
srand ( (unsigned)time ( NULL ) );

//Open output datafile
if ((outdata = fopen("triangle_data.txt","w"))==NULL)
	{printf ("\nOutput file cannot be opened.\n");
	exit (1);}
else
{
printf("Output file = triangle_data.txt");
}

trials = (long int)atoi(argv[1]);
iterations = (long int)atoi(argv[2]);

printf("\ntrials = %ld\titerations = %ld\n",trials, iterations);

for(j=0;j<iterations;j++)
{
triangle = 0;

for(i=0;i<trials;i++)
{
point1 = randfloat();
point2 = randfloat();
if(point1<point2)
{
side1 = point1;
side2 = point2 - point1;
side3 = 1.0 - point2;
}
else
{
side1 = point2;
side2 = point1 - point2;
side3 = 1.0 - point1;
}
t_flag = 1;
if (side1> (side2+side3)) t_flag = 0;
if (side2> (side1+side3)) t_flag = 0;
if (side3> (side1+side2)) t_flag = 0;
if (t_flag ==1) triangle++;
}

percentage = 100* (float)triangle/trials;

fprintf(outdata,"%f\n",percentage);
printf("%f\n",percentage);
}


//Close output file
fclose(outdata);

return (0);

}