Why do I get an “undefined identifier” error even though the variable is defined in my code?

Question

I've been trying to get the Mario problem finished. What appears to me to be a workable solution keeps generating error messages (when I run the compiler) around an "undeclared identifier" (even though I have clearly defined the integer, namely height) and one relating to "expected expression" when using the "height > 0 && < 24" function in a while loop.

I've looked at the other answers on this forum on pset1 Mario but nothing seems to directly address my problem. Why am I getting these errors?

int main(void) 
{   
    do  {
        printf("Enter the height of the pyramid: \n");
        int height = GetInt();
        }
    while (height > 0 && < 24);
}

Answer 1

In C all variable names have to be declared before they are used. If you try to use the name of a variable or a function that hasn't been declared you will get an "undeclared identifier" error.

• You issue deals with scoping. To fix your issue you need to declare the variable height before the while lope.

Your code should be the following:

int height;
  do {
    height = Getint();
} while (some condition);