Loop skips scanf instruction after first time
Here is the code for main ():
int main (void)
{
float acres[20];
float bushels[20];
float cost = 0;
float pricePerBushel = 0;
float totalAcres = 0;
char choice;
int counter = 0;
for(counter = 0; counter < 20; counter++)
{
printf("would you like to enter another farm? ");
scanf("%c", &choice);
if (choice == 'n')
{
printf("in break ");
break;
}
printf("enter the number of acres: ");
scanf("%f", &acres[counter]);
printf("enter the number of bushels: ");
scanf("%f", &bushels[counter]);
}
return 0;
}
Every time the program goes through the first scanf works fine, but the second time through the loop, scanf does not run for character input.
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Add a space before %c
in scanf
. This will scanf
allow any number of spaces to be skipped before reading choice
.
scanf(" %c", &choice);
is the only change.
Adding a fflush(stdin);
before scanf("%c", &choice);
will also work. fflush
the call will clear the contents of the input buffer before reading the next input through scanf.
In case scanf(" %c", &choice);
, even if there is only one character in the read input buffer, it scanf
will interpret this character as valid user input and continue execution. Incorrect use of scanf can lead to a number of strange errors (eg infinite loops when used inside a loop while
).
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