how do i put a loop around a switch statement?

[caffrea4]

i have the following switch statement to provide a menu. I want the menu to appear again after each selection. I tried using a "do - while" loop but it didn't work. :(

switch ( choice )

{
case 1:
norecs = read_info("year2009.txt", res);
break;


case 2:
compute(hotel_type res[], int size);
break;


case 3:
compute_total(hotel_type res[], int size);
break;


case 4:
print_res (hotel_type res[], int size);
break;


case 5:
write_records (“week2009.txt”, res, norecs);
break;


default:
printf ("invalid Choice");
break;
}

[Disch]

do
{
  // .. the stuff you want to loop
}while( /*you want to keep looping*/ );

[bolohardik]

Hi caffrea4
As Disch said, do while loop must work provided you mention the exit condition otherwise it will go into the infinite loop.

[caffrea4]

I tried that. When i put in my choice the cursor just moves to the next line and the menu doesn't appear again. It doesn't let me enter anything i have to end the program.. what's wrong

[Disch]

Did you put your menu code in the loop?

If you want it to repeat (loop), then it belongs in the loop.

[caffrea4]

Yeah this is how i put it in :

do
{

printf ("welcome to my program\n\n");
printf ("MENU\n\n");
printf ("1.\tRead data from files\n");
printf ("2.\tcompute total number of booked days for 2009 and 2010\n");
printf ("3.\tCompute total amount received by hotel\n");
printf ("4.\tShow on screen the details of persons who paid over 1000 euro\n");
printf ("5.\tSave data to file: week2009.txt\n\n");
printf ("Please enter your choice.\n\n");

scanf ("%d", &choice);

switch ( choice )

{
case 1:
norecs = read_info("year2009.txt", res);

break;


case 2:
compute(res, 100);


break;


case 3:
compute_total(res, 100);
break;


case 4:
print_res (res, 100);
break;


case 5:
write_records ("week2009.txt", res, norecs);
break;


default:
printf ("invalid Choice");
break;
}
} while (choice <5);

Why is it just stopping when i enter a choice. Thanks for the replies by the way

[Null]

compute(hotel_type res[], int size);
Wrong code. I think you want

hotel_type res[100];// declare res
int size=100;  
// ...

compute(res,  size);

Btw, use [code] [/code] tags

EDIT: too late
EDIT_2: maybe there's something wrong with one of the functions. Also try to enter an invalid choice - if program quits then do-while loop is OK.

[caffrea4]

I modified it to what you said but i get errors in compile :

Error E2108 program.c 68: Improper use of typedef 'hotel_type' in function main
Error E2121 program.c 68: Function call missing ) in function main
*** 2 errors in Compile ***

[caffrea4]

yeah when I put in an invalid choice the program ends, which is what i want so the loop works but my program doesn't??

[Null]

Can you post more code?

[caffrea4]

ok here is the entire code, I'm useless

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


typedef struct hotel_tag

{

char surname[20];
char first_name[20];
int year_in;
int year_out;
int month_in;
int month_out;
int day_in;
int day_out;
int num_days;
float price;
float tot_price;

} hotel_type;



int read_info(char* file_name, hotel_type res[]);

void compute(hotel_type res[], int size);

void compute_total(hotel_type res[], int size);

void print_res (hotel_type res[], int size);

void write_records (char* file_name, hotel_type res[], int size);


int main()

{
 
hotel_type res[100];
int norecs;
int choice;

do
{

printf ("welcome to my program\n\n");
printf ("MENU\n\n");
printf ("1.\tRead data from files\n");
printf ("2.\tcompute total number of booked days for 2009 and 2010\n");
printf ("3.\tCompute total amount received by hotel\n");
printf ("4.\tShow on screen the details of persons who paid over 1000 euro\n");
printf ("5.\tSave data to file: week2009.txt\n\n");
printf ("Please enter your choice.\n\n");

scanf ("%d", &choice);

switch ( choice ) 

	{
		case 1:
  			norecs = read_info("year2009.txt", res);
			
 		break;
			

		case 2:
 			compute(res, 100);
			
			
 		break;


		case 3:
 			compute_total(res, 100);
 		break;


		case 4:
 			print_res (res, 100);
 		break;


		case 5:
 			write_records ("week2009.txt", res, norecs);
 		break;


		default:
  			printf ("invalid Choice");
  		break;
	}
} while (choice <5);
return (EXIT_SUCCESS);

}


int read_info(char* file_name, hotel_type res[])

{

FILE* fp;
int norecs;
char ch;

fp = fopen(file_name, "r");

while (!feof(fp))
	
	{
	
	fscanf (fp, "%c%c%d%d%d%d%d%d%f", &res[norecs].surname, 
					  &res[norecs].first_name,
					  &res[norecs].year_in,
					  &res[norecs].month_in,
					  &res[norecs].day_in,
					  &res[norecs].year_out,
					  &res[norecs].month_out,
					  &res[norecs].day_out,
					  &res[norecs].price);

	norecs++;

	}
fclose(fp);

return norecs;

}







void compute(hotel_type res[], int size)

{

int i;

for (i=0; i < size; i++)

	if (res[i].day_out > res[i].day_in)

		res[i].num_days = res[i].day_out - res[i].day_in;

	else

		res[i].num_days = res[i].day_out + (30 - res[i].day_in);

}






void compute_total(hotel_type res[], int size)

{

int i;

for (i=0; i < size; i++)

	res[i].tot_price = res[i].num_days * res[i].price;


}





void print_res (hotel_type res[], int size)

{

int i;

printf ("\t| Surname\t | First name\t | Total amount |\n\n");

	for(i=0; i < size; i ++)

		if (res[i].tot_price > 1000)

		printf ("\t| %s\t | %s\t | %f", res[i].surname, res[i].first_name, res[i].tot_price);

}





void write_records (char* file_name, hotel_type res[], int size)

{

FILE* fp;

int i;


fp = fopen(file_name, "w");


for (i = 0; i < size; i++)

fprintf (fp, "%s %s %f \n", res[i].surname, 
			    res[i].first_name,
			    res[i].tot_price);


fflush(fp);



fclose(fp);

}

[pyschoder]

line 104... norecs has no initial value