C / C++ / MFC

// file myfun.h
int square(int x);

// file myfun.cpp
#include <iostream>
#include "myfun.h"
void main()
{
  int n;
  n = 5;
  std::cout << "square of " << n << " is " << square(n) << std::endl; 
}
int square(int x)
{
  return x*x;
}
</iostream>

CPallini wrote:

(1) You really need good C++ book.

CPallini wrote:

// file myfun.h
int square(int x);

// file myfun.h
#pragma once    //or anything similar
 
int square(int x);

toxcct wrote:

to be exact, the header file should be:

toxcct wrote:

for my part, i'd even prefer to see the function delaration in its own header (like you do), but its definition in another compilation unit than main()...

savitri wrote:

i have one more problem in my program.. how to define and declare the new function.

savitri wrote:

but i know c++

li zhiyuan wrote:

Y = 0.3*R + 0.59*G + 0.11*B, the error occurred below:

error C2440: '=' : cannot convert from 'unsigned int' to 'unsigned int *'?

for (ctr=0; ctr <=15; ctr++)
{
 dout[ctr]=' ';
}
for (ctr=0; ctr <strlen(strData); ctr++)
{
  dout[ctr] = strData[ctr+1];
}