Thread: Loop problem

Originally Posted by Tesnik

by the way, how long do i have to study to start making more complicated programs. I mean serious programs??

you are already. programming is serious buisness.

no, seriously, it can take a while. but it really depends on what you say is serious.

You could make it really complicated with threading, networking, advanced data structures, graphics, shared libraries, STL, etc, or you could make a useful console program. but each additional facet of programming besides (well, including) standard C++ takes a while to learn to use effectively, but they all build upon C++, so you should have a solid understanding of the core language first. Each of these things can take months, or even years, to learn how to do well.

Here's some stuff you might find useful:

<< !! Posting Code? Read this First !! >>
Cprogramming.com: How to Get Started with C++
Cprogramming.com - Programming Tutorials: C++ Made Easy and C Made Easy
Cprogramming.com: FAQ
C Book Recommendations
C++ Book Recommendations - C Board
cplusplus.com - The C++ Resources Network

or there's the classic:

Code:

#include <iostream>
#include <vector>
#include <algorithm>
#include <functional>

using namespace std;

int num = 0;

void Add( int i )
{
   num += i;
}

int main()
{
   vector<int> vec;

   for ( int i = 1; i <= 10; ++i )
   {
      vec.push_back( i );
   }

   for_each( vec.begin(), vec.end(), Add );

   cout << num << endl;

   return 0;
}

or good old:

Code:

#include <iostream>

using namespace std;

int main()
{
   int n = 0;
   for ( int i = 1; i <= 10; n += i++ );

   cout << n << endl;

   return 0;
}

haha thanks cpjust i appreciate it

robwhit i have answered you on top of cpjust, we must have press the post button at the same time

cpjust what does n+= mean?

I sure will

Do you realize that all of the answers that cpjust has given are much more complicated than you need? If you're trying to learn, you should keep looking for the right answer yourself.

If you know a for loop, try and use it. Otherwise, keep working on your while loop.

umm yeah, but its good to know what n += i++ means, or why doesn't the cout go inside the for loop.

The cout is outside the for loop, meaning it is run only once. The cout outputs the end result, so you want it to run only once. If you put it inside the for loop, it would run each time through the loop, and you would get 1, 3, 6, 10, ...

n += i++ has two parts. The first part is the i++. i++ means add 1 to i, but it also returns a value. It reutrns the value of i before you add one. So lets say i is 0, then i++ returns 0 and changes the value of i to 1.

The second part is the n += part. That means that whatever i++ returns is added to n. Since we just learned that i++ returns the value of i before 1 is added, then n += i++ adds the value of i to n, then adds 1 to i.

In the normal for loop, those two parts would be separated for clarity and readability.

very clear, thanks.

lol @ cpjust being a showoff.

Yeah, I saw everybody giving Tesnik half of the answer at a time, so I figured I might as well try to completely confuse him and give him every answer except the simple one. Sometimes I get evil when I'm bored.

and i thought you were being a good, kind person