Question

The following code snippet is free of errors (issues that will prevent the code from compiling) but it does contain a major bug that will cause the program to hang (not finish running). Identify the problem and create a line of code to fix it.

#include <stdio.h>

char get_input();

int main() {
    printf("The user's inputted letter is %c\n", get_input());
    return 0;
}

char get_input() {
    printf("Please enter a letter: \n");
    char input = getchar();
    
    while (!(input >= 'a' && input <= 'z') && !(input >= 'A' && input <= 'Z')) {
        printf("You did not enter a letter! Try again\n");
    }
    
    return input;
}

Answer 1

Answer

Here is your answer, if you have any doubt please comment, i am here to help you.

here is your fix for the above problem.

ERROR

•   while (!(input >= 'a' && input <= 'z') && !(input >= 'A' && input <= 'Z')) {
          printf("You did not enter a letter! Try again\n");
      }
  
  /*there is no exit for the above while loop, any while loop or for loop there must be a terminate statement.
  
  Here you don't need while loop, just only enough if statement. 
  
  If your are using while just add break after printf()*/

FIX

#include <stdio.h>

char get_input();

int main() {
    printf("The user's inputted letter is %c\n", get_input());
    return 0;
}

char get_input() {
    printf("Please enter a letter: \n");
    char input = getchar();
    //just change while loop to if, then not use break
    while (!(input >= 'a' && input <= 'z') && !(input >= 'A' && input <= 'Z')) {
        printf("You did not enter a letter! Try again\n");
        //break;  //use break if while loop using, 
    }
    
    return input;
}

output

Any doubt please comment,

Thanks in advance