random.c

//testing the gist
/* random.c
 *
 * Copyright (C) 2012-2018 by Henry Kroll III, www.thenerdshow.com
 * 
 * This program 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.
 * 
 * This program 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/>.
 */
#include <stdio.h>
#include <stdarg.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <math.h>
#include <sys/time.h>
#define _STR(a) #a
#define STR(a) _STR(a)
#define LET(a) if (!(a)){ \
    perror(__FILE__":"STR(__LINE__));exit(1);}
#define FREE(a) free(a);a=NULL;
int runs=400, ceiling=56000.0;
double goal=.1, mult=1.147, startbet=.007, minbet=.7, tax=.0005, maxbet=500000, biggestloser=0;
//~ randinit
void randinit() {
	struct timeval tv; 			/* seed srand() */
	gettimeofday (&tv,0); /* with something... */
	srand ((unsigned int)tv.tv_usec);
}
double getrand(double low, double high) {
    return high*(rand()/(RAND_MAX+1.0))+low;
}
 //{ main
int main (int argc, char **argv) {
    int roll, j, win=0, losses=0;
    double grand=0.0,take=0.0, bet=startbet;
    randinit ();
    for (j=0;j<runs;j++) {
        while (take<0.0999&&take>=-999.0) {
            roll=getrand (0.0,65535.0);
            if (roll<=ceiling) {
                take+=bet*(mult-1);
                win=1;
            }
            else {
                take-=bet;
                win=0;
            }
            take-=tax;
            if (runs<5||take>1.0) {
                printf ("%5s %-4.3f, take %.4f\n",win?"won":"lost", bet, take);
            }
            
            //~ bet=getrand(minbet,maxbet)
            bet=(fabs(take)+tax+goal)/(mult-1.0);
            if (bet<minbet||win) bet=minbet;
            if (bet>maxbet) bet=maxbet;
        }
        if (runs<5) printf ("ending take: %.4f\n",take);
        if (take<0) {
            losses++;
            if (biggestloser>take) biggestloser=take;
        }
        grand+=take;
        take=0.0;
        bet=startbet;
    }
    printf ("total: %.4f avg: %.4f loss%%: %.2f most: %.4f\n",grand,grand/runs, (float)losses/(float)runs*100.0,biggestloser);
    return 0;
}
//} main