Thread: Program skipping input....Scanf()

  1. #1
    Registered User
    Join Date
    Nov 2010

    Question Program skipping input....Scanf()

    #include <stdio.h>
    int _1st, end;
    char letter;
    int main(void)
    scanf("%d", &_1st);
    scanf("%d", &end);
    scanf("%c", &letter);
    printf("_1st = %d\n", _1st);
    printf("Letter = %c\n", letter);
    printf("_2nd = %d\n", end);

    The code above has been causing me a lot of trouble. ANY help would be appreciated.
    I am new to C programming, as the code above may indicate, and I want to collect two numbers (the first two scanf()s) and then a letter (the third scanf() ). However, it seems as if the program completely skips the letter step and advances to displaying what was entered, not even giving a chance to enter the letter. What is going on? Is it my compiler or just me?

    THE OUTPUT FOR 8 and 20, for example:

    8 20
    _1st = 8
    Letter =

    _2nd = 20

  2. #2
    Just a pushpin. bernt's Avatar
    Join Date
    May 2009
    8 20
    _1st = 8
    Letter =

    _2nd = 20
    scanf leaves a newline in the input, which is being picked up when you read in a character, and this is being printed out. That also accounts for the mysterious blank line between "Letter" and "_2nd".

    You can get around this by enforcing some limits on what letter can be:
    while (!isprint(letter)) {
    or something to that effect.
    Consider this post signed

  3. #3
    Registered User hellork's Avatar
    Join Date
    Nov 2010

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