C++

[tip32926]

cout << "Input file: ";
fstream in(cin.getline(filename,80));


im trying to use what the user enters as the input and output

thanks for your help

[ColdShadow]

Code: Select all

#include <cstdio>
#include <cstdlib>
#include <iostream>
using namespace std;

int main(int nNumberofArgs, char* pszArgs[])
{
   
    string var;
    cout << "Enter in a number:";
    cin >> var;
    cout << var;

    system("PAUSE");
    return 0;
}

We can get input as a variable by using cin.

[cheryl]

Code: Select all

#include <cstdio>
#include <cstdlib>
#include <iostream>
using namespace std;

int main(int nNumberofArgs, char* pszArgs[])
{
   
    string var;
    cout << "Enter in a number:";
    cin >> var;
    cout << var;

    system("PAUSE");
    return 0;
}

We can get input as a variable by using cin.

I know next to nothing about C++.

Can you tell me the purpose of the iostream include? I've noticed that it must be present for even the simplest program.

And by the way, welcome to our forum : )

[Astronut]

Code: Select all

#include <cstdio>
#include <cstdlib>
#include <iostream>
using namespace std;

int main(int nNumberofArgs, char* pszArgs[])
{
   
    string var;
    cout << "Enter in a number:";
    cin >> var;
    cout << var;

    system("PAUSE");
    return 0;
}

We can get input as a variable by using cin.

I know next to nothing about C++.

Can you tell me the purpose of the iostream include? I've noticed that it must be present for even the simplest program.

And by the way, welcome to our forum : )

Woohoo! I know this one!

iostream calls a library that includes the cin, cout, and endl functions, as well as others. These are very common functions, and the only way to get them is to include iostream. There are other ways, but this seems to be the most often used.

[tip32926]

#include <iostream>
#include <fstream>
#include <string>
using namespace std;


int main()
{
char letter;
string word, namein, nameout;
vector<string> one;

cout << "Input file: ";
cin >> namein;
ifstream input(namein.c_str());

return 0;
}

this is what i used(sry i meant to post it

[ColdShadow]

know next to nothing about C++.

Can you tell me the purpose of the iostream include? I've noticed that it must be present for even the simplest program.

I quote wikipedia:

iostream is a header file which is used for input/output in the C++ programming language. The name stands for Input/Output Stream. In C++ and its predecessor, the C programming language, there is no directly-included method for streaming data input or output. Instead, these are combined as a library. iostream handles basic input and output for C++, whereas stdio.h is used in C. iostream uses the objects cin, cout, and cerr for sending data to and from the standard streams input, output, and error respectively.

iostream is only needed if the program uses cin, cout, or cerr

[cheryl]

know next to nothing about C++.

Can you tell me the purpose of the iostream include? I've noticed that it must be present for even the simplest program.

I quote wikipedia:

iostream is a header file which is used for input/output in the C++ programming language. The name stands for Input/Output Stream. In C++ and its predecessor, the C programming language, there is no directly-included method for streaming data input or output. Instead, these are combined as a library. iostream handles basic input and output for C++, whereas stdio.h is used in C. iostream uses the objects cin, cout, and cerr for sending data to and from the standard streams input, output, and error respectively.

iostream is only needed if the program uses cin, cout, or cerr

Wow! So compared to a simple language like BASIC, which uses statements like "input x" or "print x" for input and output, C++ must be extremely customize-able. If I understand you correctly, there is no built in function for user input/output, you have to call up a pre-written subroutine to get that function? And iostream is one possible example of an input/output routine, yes?

Well, I can see why operating systems are written in this language...

[ColdShadow]

Wow! So compared to a simple language like BASIC, which uses statements like "input x" or "print x" for input and output, C++ must be extremely customize-able. If I understand you correctly, there is no built in function for user input/output, you have to call up a pre-written subroutine to get that function? And iostream is one possible example of an input/output routine, yes?

Well, I can see why operating systems are written in this language...

Iostream is a library of functions you can call.

Operating systems aren't programmed in c++ silly:)

[Andre]

Operating Systems are usually written in C, not C++

[cheryl]

Wow! So compared to a simple language like BASIC, which uses statements like "input x" or "print x" for input and output, C++ must be extremely customize-able. If I understand you correctly, there is no built in function for user input/output, you have to call up a pre-written subroutine to get that function? And iostream is one possible example of an input/output routine, yes?

Well, I can see why operating systems are written in this language...

Iostream is a library of functions you can call.

Operating systems aren't programmed in c++ silly:)

Ah, I was told that Unix was written in C in 1969, and that C++ was a more modern, enhanced version of the old C language, so I thought... Also, it seems to me that everytime someone talks about making a custom kernal for their particular install of Linux, speak of compiling C++ source code. Now I'm really confused. As well as silly.

[EdTheN00bProgrammer]

http://www.cplusplus.com/reference/iostream/

It would seem that the iostream class is the parent of the istream and ostream classes.

i think that iostream stands for in/out stream, ostream stads for outstream, istream stands for instream, ifstream stands for in file stream and ofstream stands for out file stream.

C++ isn't as powerful? What makes you think that?

I'm a n00b to C++, so I'm not trying to say that C++ is as powerful; I'm just wondering.

[kingofnerds]

C++ is a higher level language, it is object oriented, whereas C is not. C relies upon loops and sequential order, C++ can be event driven. Sure you can do Event driven things with C, but it is much easier to do it with C++. Also programs written in C generally tend to run faster and take less drive space than those written in C++.

[EdTheN00bProgrammer]

To what extent?