Thread: Switch case, switch between case

Hello
I excuse my bad english.

I am trying to make a program which manages the data of 5 different patients (its an uni assignment), and i want to use a switch case as a menu to switch between the patients. All other functions (as for example putting the infromation on a file) work, but i cant figure out to bring the switch to work. First it asks for the number of the patient which should be worked with, this works perfectly, but afterwards changiung between the persons doesnt work as thought. It should ask everytime after it switches to one patient (i removed some functions to make it easier to read) and then asks to which it should jump next. If i put the number of one case (lets say 3) it just stops the program.

********Example:
user@pc ~/wherever $ ./program
current variables:
jo = 2
a = 0

1 //the entered number
The variable a = 1
patient 1
Enter the number of the next patient2
// and then it closes
**************


The same thing happens if i compile an example code from a book, it writes the first case and then stops.

I looked already through the forum but didnt find a person with a similar problem, maybe i didnt dig deep enough.

I am running Linux Mint 17 and use gcc as compiler.

Code:

include <stdio.h>
#include <stdlib.h>

int a=0;
int jo=2;

int main(void){
printf("current variables:\n jo = %d\n a = %d\n", jo, a);
scanf("%d", &a);
printf("The variable a = %d\n", a);
    switch ( a ) {
    case 1:
        printf("patient 1 \n");
        ChooseA();
    break;
    
    case 2:
        printf("patient 2 \n");
        ChooseA();
    break;
    
    case 3:
        printf("patient 3 \n");
        ChooseA();
    break;
    
    case 4:
        printf("patient 4 \n");
        ChooseA();
    break;

    case 5:
        printf("patient 5 \n");
        ChooseA();
    break;

    case 6:
        printf("Do you want to delete the collected data? 1 for yes/0 for no \n");
        jo=2;
        scanf("%d", &jo);
            if(jo == 1){
                FILE *fp;
                fp=fopen("/home/jpreissler/Skrivebord/ImperativProgrammering/database.txt", "w");
                fclose(fp);
                printf("Data deleted\n");

            }
            if(jo == 0){
                printf("No data deleted\n");
            }
            else{

            }
    break;

    default:
    printf("NUMBER NOT VALID\n");
}
return(0);
}
int ChooseA(){
    printf("Enter the number of the next patient");
    scanf("%d", &a);
}

Originally Posted by aldo_baldo

As far as I can see, looks like there are not any statements that take you back to the beginning of the switch. I think you could use while, do, for or even goto to "jump back to the beginning".

#Doesnt work#
do you mean something like

int main(){
while(a<= "someinteger")
switch ( a ) {

case 1:
printf("patient 1 \n");
a= "someinteger"++
.........

The next guy with goto.
A do-while-loop do the same thing.

Code:

do {
    scanf(" %d", &a);
    printf("The variable a = %d\n", a);
    switch ( a ) {
        case 1:
            printf("patient 1 \n");
            ChooseA();
            break;

        case 2:
            printf("patient 2 \n");
            ChooseA();
            break;

        case 3:
            printf("patient 3 \n");
            ChooseA();
            break;

        case 4:
            printf("patient 4 \n");
            ChooseA();
            break;

        case 5:
            printf("patient 5 \n");
            ChooseA();
            break;

        case 6:
            printf("Do you want to delete the collected data? 1 for yes/0 for no \n");
            jo=2;
            scanf("%d", &jo);
            if(jo == 1) {
                FILE *fp;
                fp=fopen("/home/jpreissler/Skrivebord/ImperativProgrammering/database.txt", "w");
                fclose(fp);
                printf("Data deleted\n");
            }
            if(jo == 0) {
                printf("No data deleted\n");
            }
            break;

        default:
            printf("NUMBER NOT VALID\n");
    }
} while (a != 0);

I have not check the content of the switchcases.

Originally Posted by Matticus

As mentioned, the OP should avoid using "goto". It is considered bad practice in all but a few situations. Please avoid giving advice that is bad practice to people who are learning the language.

I wrote "or even goto". "EVEN", just to point out that goto should be the last choice if while, do and for can't match one's needs. Maybe my English is poor (I'm an old Italian chap) and I didn't succeed in stating what I had in mind, but that was my intention.

Anyway, goto is not the devil. As an example, sometimes I find it useful using goto to manage errors in functions that require "cleanup" operations before returning. I don't mean that I use goto EACH TIME I have to manage errors in such funtions, but when I see the opportunity to use it I don't go and look for a priest to save my soul.

By the way, what does "OP" mean? It's an acronym I found more than once in this forum and I can guess that it's referred to the one who asked a question (more or less), but I don't know what it EXACTLY stands for.

P.S. As regards the current context, I think that you are right -- goto is utterly useless and can be easily avoided.

Originally Posted by danlee58

Should I start a new thread?

Yes, please.

If you want to quit the program with case 6, then you have to edit the while contition on last line to:

Code:

…
} while (a != 6);