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Re: cin and scanf which is best for simple input

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papoupapa wrote:

> Hi,
> 
> Can someone tell from the code below why scanf solves the issue of a
> number out of
> 
> the range and cin seems to read twice a great number such as
> 100000000000 or go into a wild loop if a character or some text is
> entered.
> 
>  #include "std_lib_facilities.h"
> 
> int main()
> {
> int val1 = 0 ;
> int val2 = 0 ;
> int nb_try ;
> bool ok = 0 ;
> 
> cout << "\nThis code reads 2 numbers and takes these 2 numbers into
> simple
> 
> processes : \n" ;
> 
> nb_try = 3 ;
> do
> {
> cout << "\nPlease enter 1st number (between 0 and 65,535) : \n" ;
> //scanf("%d", &val1) ;
> cin >> val1 ;
> 
> if ((val1 >= 0) && (val1 < 65536))

You test whether val1 is in the required range. However, you have no test 
for whether the reading from cin succeeded. You could try:

  if ( ( cin >> val1 )  &&  ( val1 >= 0 )  &&  ( val1 < 65536 ) ) {
    ...
  }

[snip]


Best,

Kai-Uwe Bux

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Thread

cin and scanf which is best for simple input papoupapa <papoupapoug@gmail.com> - 2011-06-11 03:53 -0700
  Re: cin and scanf which is best for simple input "osmium" <r124c4u102@comcast.net> - 2011-06-11 12:06 -0500
    Re: cin and scanf which is best for simple input "Sprechen Sie C++" <spamabuse@hotmail.com> - 2011-06-11 10:50 -0700
  Re: cin and scanf which is best for simple input Kai-Uwe Bux <jkherciueh@gmx.net> - 2011-06-11 20:29 +0200
    Re: cin and scanf which is best for simple input papoupapa <papoupapoug@gmail.com> - 2011-06-12 16:25 -0700

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