C/C++ Using cin to Read Integers in Formation a@b in C++

[YoungPhysicist]

if I want to read to integer a and b and they are in a formation of a@b, I CAN SIMPLY USE

scanf(%d@%d,&a,&b)

to read the input. But how should I do that in c++(with cin)?

 

[FactChecker]

cin is not a good way to get multiple inputs that are not separated by space directly into variables. It is better to read the input into a string and parse it at your leisure. See stringstream: http://www.cplusplus.com/doc/tutorial/basic_io/. Alternatively, there are usually ways to make your C code work in C++ (but C strings are a little harder to use in C++ than number types).

 

[jedishrfu]

I would get familiar with string methods and read the input into a string that you can then parse anyway you want.

As an example, you might want to input time values allowing either a decimal format or the hour:minute:second format. String methods would give you the flexibility you’d need to parse the input.

 

[FactChecker]

As an example, you might want to input time values allowing either a decimal format or the hour:minute:second format. String methods would give you the flexibility you’d need to parse the input.

Agree. Especially since one can try parsing one way, test for an error, and parse another way if necessary.

 

[jedishrfu]

Here's a tutorial on string methods in C++:

https://cal-linux.com/tutorials/strings.html

It mentions regular expressions and using the Boost library too. Regular expressions can dice up some pretty fancy string formats and is a useful skill for using GREP, SED or AWK commands in shell scripts (or not) under Unix / MacOSX / Linux.

 

[YoungPhysicist]

Here's a tutorial on string methods in C++:

https://cal-linux.com/tutorials/strings.html

It mentions regular expressions and using the Boost library too. Regular expressions can dice up some pretty fancy string formats and is a useful skill for using GREP, SED or AWK commands in shell scripts (or not) under Unix / MacOSX / Linux.

Is the <boost/regex.hpp> it mentioned in the standard library?

 

[jedishrfu]

No I think boost is a third party library that you must download and install to use it.

 

[Svein]

As an example, you might want to input time values allowing either a decimal format or the hour:minute:second format. String methods would give you the flexibility you’d need to parse the input.

strtok() comes to mind...