codebreak.c

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


int need_space_int(int i)
{
  if (!i)
    return 1;

  unsigned int j=1;
  int space = 1;
  while (j<=abs(i))
  {
    space++;
    j*=10;
  }
  return space;
}


int main(int argc, char *argv[])
{
  srand(time(NULL));
  printf("Welcome to CodeBreak (http://houbysoft.com/en/downprog.php#codebreak).\nStart guessing, or type '?' or 'h' for quick help.\n");
  int min = 1000;
  int max = 10000;
  int deduceme;
  char *deducestr;
  char *statusstr;
  char again = 1;
  while (again)
  {
    while (1)
    {
      deduceme = rand() % (max - min) + min;
      deducestr = malloc(need_space_int(deduceme)+1);
      statusstr = malloc(need_space_int(deduceme)+1);
      if (!deducestr || !statusstr)
      {
	printf("Error : cannot allocate enough memory. Something is probably very wrong; closing.\n");
	exit(1);
      }
      sprintf(deducestr,"%i",deduceme);
      int i=0;
      char digits[10];
      memset(&digits, 0, 10);
      for (; i<strlen(deducestr); i++)
      {
	if (digits[deducestr[i]-48]==1)
	{
	  free(deducestr);
	  free(statusstr);
	  deduceme = 0;
	  break;
	}
	else
	  digits[deducestr[i]-48]=1;
      }
      if (deduceme == 0)
	continue;
      else
	break;
    }
    sprintf(statusstr,"");
    int tries_remain = 12;
    int guess = -1;
    while (tries_remain)
    {
      printf("[%s] (%i %s)\n\n",statusstr,tries_remain,tries_remain == 1 ? "try remains" : "tries remain");
      char *guessstr = malloc(need_space_int(max)+1);
      if (!guessstr)
      {
	printf("Error : cannot allocate enough memory. Something is probably very wrong; closing.\n");
	exit(1);
      }
      char first = 1;
      guess = -1;
      while (!(guess >= min && guess < max))
      {
	if (!first)
	  printf("Wrong format. Your guess needs to be an integer >= %i and < %i.\n",min,max);
	first = 0;
	fgets(guessstr,need_space_int(max)+1,stdin);
	guessstr[need_space_int(max)] = 0;
	if (guessstr[strlen(guessstr)-1]=='\n')
	  guessstr[strlen(guessstr)-1]=0;
	else
	  first = 1;
	if (strcmp(guessstr,"h")==0 || strcmp(guessstr,"?")==0)
	{
	  printf("This game is really simple.\nYour goal is to deduce, by logic, the number the computer is 'thinking'. To do that, you can enter a 4-digit number 12 times.\nEvery entry will get evaluated by the computer and you will get a response in the form of circles, stars, and minuses.\nA star means that in your response, a number is in its correct position.\nA circle means that you included a correct number in your try, but it is not in the correct position.\nMinuses represent the number of numbers that you entered but are not in the answer.\n\nNote that these 'ratings' are not necessarily in the correct order. For example, if the answer is 1234, and you enter '5612', you will get a rating of [oo--], instead of [--oo], as you might have thought.\n\nGood luck, enter your first try!\n");
	  first = 1;
	}
	guess = atoi(guessstr);
      }
      if (guess == deduceme)
	break;
      else
      {
	int i=0;
	int correct_pos = 0;
	int correct_num = 0;
	for (; i<strlen(guessstr); i++)
	{
	  if (strchr(deducestr,guessstr[i]))
	  {
	    if ((strchr(deducestr, guessstr[i]) - deducestr) == i)
	    {
	      correct_pos += 1;
	    } else {
	      correct_num += 1;
	    }
	  }
	}
	int incorrect = strlen(deducestr) - correct_pos - correct_num;
	strcpy(statusstr,"");
	while (correct_pos--)
	  strcat(statusstr,"*");
	while (correct_num--)
	  strcat(statusstr,"o");
	while (incorrect--)
	  strcat(statusstr,"-");
	free(guessstr);
      }
      tries_remain--;
    }
    if (tries_remain)
    {
      printf("Congratulations; you won. You had %i more %s.\n",tries_remain-1,tries_remain-1 == 1 ? "try" : "tries");
    } else {
      printf("You lost; the answer was %i.\n",deduceme);
    }
    again = 0;
    printf("Do you want to play again? (yes/no) ");
    char ans[5];
    fgets(ans,5,stdin);
    if (strcmp(ans,"yes\n")==0)
      again = 1;
    else
      again = 0;
    free(deducestr);
    free(statusstr);
  }
  return 0;
}