My program skip getting input data? [duplicate]

Answer 1

I was wondering why you made 'choice' a float, not an int Also, consider using a switch-case that way, you won't have to do the whole do-while loop. Also, in the line printf ("\nWould you like to buy a beer (y/n) ?",buy); Why did u add that? Here is what I would have done :

printf("Your choice?\n>");
scanf("%d", &choice);

switch(choice)
{
     case 1 :
    {
         out_c = in_c / ex_rate_into_vnd;
            printf ("Your amount of money: %.2f",out_c);


    }

     case 2:
    {

    out_c = in_c * ex_rate_into_vnd;
           printf ("Your amount of money: %.0f",out_c);

    }

    default :
    printf("\nThere has been an error\n"):
    reloadprogram();   /* Reloadprogram() is simply to make this go back to the asking thing :) */

}

}

EDIT: also, where it says if( <somevariable> >= 7000), change 7000 to beer, so that way, if u change beer, you won't have to change this :)

Answer 2

Instead of scanf("%c", &buy);

1.use space before %c

scanf(" %c",&buy); //space before %c  
       ^ 

this skips reading of white space (including newlines).

2.or Use getchar(); before scanf("%c", &buy); statement

getchar(); //this hold the newline 
scanf("%c", &buy);

3.or use two times getchar();

getchar();
buy=getchar();     
//here getchar returns int , it would be better if you declare buy with integer type.

In GCC usage of fflush(stdin); is discouaraged. please avoid using it.

Answer 3

You have at least one \n between the latest float entry and the char you want to read. You need to get rid of that first.

See also all answers in getchar after scanf category

Answer 4

Put a fflush(stdin) to clear the input before the last scanf

Answer 5

The program doesn't skip the third input data, it just scans the newline you press after the second input. To fix this, type scanf("%*c%c", &buy); instead of scanf("%c", &buy);. This little %*c scans and ignores the the character read from the input.

Answer 6

you can remove the buy variable from the printf call, it's unneeded

printf ("\nWould you like to buy a beer (y/n) ?",buy);

And replace char buy by char buy[2]; . because a sting is always terminated by /0.

You can also add a memset (buy, 0, sizeof(buy)), to be sure that memory is reset before you start to use it.