programm in c (go a round in a room) [closed] - c

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I have a little problem with a C-programm, I wrote. It should be like "you go in a room.. is there a wall? no? then move on.. is there a wall? yes? then turn around" and so on. I am stucked, I go in the room and turn around but do not know how to go further.
#include <stdio.h>
void main()
{
char answer[2];
answer[0] = "Y";
answer[1] = "N";
do
{
printf("Move!\n");
printf("Is there a wall?\n");
scanf("%s",answer);
}
while (answer[0] != 'Y' );
printf("Turn around!");
}
I read about loops and ifs, but my head do not make klick.
Thanks for reading,
hjerteblod

Answer 1

Assuming you want to never exit the game. If so, try this code -
#include <stdio.h>
int main()
{
char answer;
while(1){
printf("Move!\n");
printf("Is there a wall?\n");
scanf(" %c", &answer);
if (answer == 'Y'){
printf("Turn around!\n");
}
}
return 0;
}

Answer 2

"Y" is a string with two characters, answer[0] is a character, you cannot assign a string to a character. So you can change this code like this answer[0] = 'Y'.
By the way, you are better to return an int value in the function main.
include <stdio.h>
int main(){
// your code here
return 0;
}

Answer 3

"N" is a string literal, which evaluates to a pointer to the first element of the string literal "Y" in memory. If you try to assign it to answer[0] you invoke undefined behavior, since you assign a address value to char objects.
The same goes for answer[1] = "N";.
Both assignments, answer[0] = "Y"; and answer[1] = "N"; should have give you a warning, like this from GCC:
warning: assignment to 'char' from 'char *' makes integer from pointer without a cast
Never ignore compiler warnings.
You don't need an array at all, use a single char for answer.
You need an infinite loop for always going further or turning back from a wall, here implemented by while (1).
Note that this is an unfinished algorithm. In a real production program you need a condition to break out of the loop. But just for the sake of your issue, here is want I think you need:
#include <stdio.h>
int main (void)
{
char answer;
while (1)
{
printf("Move!\n");
printf("Is there a wall?\n");
if ( scanf(" %c", &answer ) != 1 )
{
fputs("Error at input!", stderr);
return 1;
}
if ( answer == 'Y' )
{
printf("Turn around!\n");
}
}
}
Side Notes:
Always check the return value of input functions such as scanf() if an error occurred.
void main() is not standard compliant. Use a return type of int and declare the parameter list of type void instead of to leave it empty.
I recommend you to read a good C starting book, f.e. Modern C by Jens Gustedt or The C Programming Language Second Edition by the inventors of C.
For more information about undefined behavior, take a look at this SO question:
Undefined, unspecified and implementation-defined behavior