Thread: Doubt with scaning characters

Hi all, for a CS project I need to make a menu, so the user must input values from 1 to 12 and q to exit the program.

My main problem is that I am using getchar() to scan the menu selection.

So inputs from 1 to 9 and q works, but 10 to 12 doesn't since getchar only supports ONE character.

My first changes were to establish the switch cases to integers between range of 10 to 12.

But still I need a suggestion of how to make the input 10, 11 and 12 to work.

Here is the code:

Code:

#include <stdio.h>
#include <stdlib.h>
#include "prints.h"
#include "exams.h"
#include "guessyn.h"
#include "guessmn.h"
#include "diceg.h"
#include "largestn.h"
#include "distance.h"
#include "areapara.h"
#include "areatrape.h"
#include "perimepoly.h"
#include "arrayv.h"
#include "arrayc.h"

int main ()
{
	int selection;
	do{
	printf("Choose a skill to practice:\n");
	printf("1) Print shapes\n");
	printf("2) Exam score\n");
	printf("3) I guess your number\n");
	printf("4) Guess my number\n");
	printf("5) Dice game\n");
	printf("6) Largest number\n");
	printf("7) Distance\n");
	printf("8) Area of parallelogram\n");
	printf("9) Area of trapezoid\n");
	printf("10) Perimeter of polygon\n");
	printf("11) Array vowel\n");
	printf("12) Array consonant\n");
	printf("q) Quit\n");
	printf("\n");
	printf("Enter selection: ");
	selection = getchar();
	while ( getchar() != '\n');
	while ( selection != '1' && selection != '2' && selection != '3' && selection != '4' && selection != '5' && selection != '6'
	&& selection != '7' && selection != '8' && selection != '9' && selection != 10 && selection != 11 && selection != 12
	&& selection != 'q' )
	{
		printf("\n");
		printf("Wrong input!!! Please try again...\n");
		printf("\n");
		printf("Enter selection: ");
		selection = getchar();
		while ( getchar() != '\n');
	}
	printf("\n");
	switch( selection ){
	case '1': prints(); break;
	case '2': exams(); break;
	case '3': guessyn(); break;
	case '4': guessmn(); break;
	case '5': diceg(); break;
	case '6': largestn(); break;
	case '7': distance(); break;
	case '8': areapara(); break;
	case '9': areatrape(); break;
	case 10: perimepoly(); break;
	case 11: arrayv(); break;
	case 12: arrayc(); break;
	case 'q': 
		printf("Thanks for playing!");
		return EXIT_SUCCESS;
	}
	printf("\n");
	}while( selection == selection );
}

Changes I made are in red

Originally Posted by laserlight

Ah yes, I did not notice that. In that case, you have do a little parsing, methinks. Read the input as a string, then determine if it is a number or a letter. If it is a letter, that is easy, you just use it. If it is a number, you then convert it to the number value, e.g., by using strtol() (which can actually be used to determine if the input is a number).

Thanks! Can you give me an example of how to use strtol().

Originally Posted by BEN10

strtol

Thanks!