Question :
I’m trying to make the game cho-han bakuchi in C. It is very simple, the Japanese game consists of throwing two 6-sided dice in a cup, before the dice are shown the player makes the bet saying cho (pairs) or han (odd). Then it shows the data and the values are summed.
What am I missing in my code?
I would not like the full code, just from the point where I’m making a mistake.
#include <stdio.h>
#include <stdlib.h>
int main()
{
int i,x,apost,cred=100,result=0;
while(apost!=EOF)
{
printf("faça a aposta:(digite -1 para sair)n");
scanf("%d", &apost);
cred=cred-apost;
printf("escolha 1-cho(par) 2-han(impar):n");
scanf("%d", &x);
switch(getc(x))
{
case 1:
i=2+rand()%12;
printf("n%10d", i);
if(i%2==0)
{
printf("ganhou!n");
cred=cred+(apost*2);
}
else
printf("perdeu!");
break;
case 2:
i=2+rand()%12;
printf("n%10d", i);
if(i%2!=0)
{
printf("ganhou!n");
cred=cred+(apost*2);
}
else
printf("perdeu!");
}
}
return 0;
}
Answer :
Always compile using warnings! If you use GCC or Clang, pass this option: -Wall to enable all principals. You can add% with% to get even more alerts. They would point out some of the mistakes I’m going to list:
Uninitialized variable:
You declared the variable -Wextra and then read its value: int apost . Reading the value of a variable without first giving it a value is invalid, its executable can do anything. In practice, this condition can give true or false in an unpredictable way. Always initialize your variables!
Test EOF on a while(apost!=EOF) :
int is an integer, stores the value of the bet. apost reads a number. On the other hand scanf("%d", &apost); is a EOF that indicates end of reading and will never be returned by scanf if you asked for a number. Consider using the following logic:
while (true) {
int apost;
printf("faça a aposta:(digite -1 para sair)n");
scanf("%d", &apost);
if (apost < 0) break;
/* ... */
}
char returns a letter, not a number:
Understand that getc is not is the same as '3' . The first is a letter, which is equivalent to the integer 53 on most systems (if you use ASCII). You should test for the letters in your switch, like this: 3 .
Probability distribution:
The sum of two random numbers from 1 to 6 is different from a random number of 2 to 12. This is because combinations that result in 5, for example are much more likely than combinations that result in 2. To form 5 we can have: 1 + 4, 2 + 3, 3 + 2, 4 + 1. While 2 may be only 1 + 1. So it will be 4 times more likely. This is the so-called normal distribution. The correction, however, is simple: generate the two values separately and then add up.