Just a quick recap:

- I'm learning C++ because of an event that took place in my life which made me look back at the past ten years. That made me think of what I could have done in those ten years.
- I've been at this for a little over a month.
- I'm using this blog as a personal/public journal on what I've learned so far. My hope is that friendly netizens will pop in from time to time to offer a word of advice or just shoot the breeze about coding.
- My ultimate goal is to not give up. This blog worked for helping me to stay focused with finishing a game. I'm hoping it will help keep me on track with learning C++ and in ten years time I can look back at these first blog posts and think what a NOOB I was.
- Lastly, this blog will help me review what I've learned.

Now onto the source code: Arithmetic

*#include <iostream>*

*using namespace std;*

*int main()*

*{*

*cout << "5 + 5 = " << 5 + 5 << endl;*

*cout << "5 - 5 = " << 5 - 5 << endl;*

*cout << "5 * 5 = " << 5 * 5 << endl;*

*cout << "5 / 5 = " << 5 / 5 << endl;*

*cout << "5.0 / 6.0 = " << 5.0 / 6.0 << endl;*

*cout << "5 / 6 = " << 5 / 6 << endl;*

*cout << "5 + 5 * 5 = " << 5 + 5 * 5 << endl;*

*cout << "(5+5) * 5 = " << (5 + 5) * 5 << endl;*

*cout << "5 % 5 = " << 5 % 5 << endl;*

*system("PAUSE");*

*return 0;*

*}*

This bit of source code will display:

**5 + 5 = 10**

**5 - 5 = 0**

**5 * 5 = 25**

**5 / 5 = 1**

**5.0 / 6.0 = 0.833333**

**5 / 6 = 0**

**5 + 5 * 5 = 30**

**(5 + 5) * 5 = 50**

**5 % 5 = 0**

First thing to note is that there are no new lines between any of the arithmetic problems even though I put spaces between some of them. Example:

*cout << "5 + 5 = " << 5 + 5 << endl;*

*cout << "5 - 5 = " << 5 - 5 << endl;*

*cout << "5 * 5 = " << 5 * 5 << endl;*

*cout << "5 / 5 = " << 5 / 5 << endl;*

*cout << "5.0 / 6.0 = " << 5.0 / 6.0 << endl;*

*cout << "5 / 6 = " << 5 / 6 << endl;*

Displays:

**5 + 5 = 10**

**5 - 5 = 0**

**5 * 5 = 25**

**5 / 5 = 1**

**5.0 / 6.0 = 0.833333**

**5 / 6 = 0**

That might not seem like a big deal, but if you don't tell the compiler that you want a space then it will not create any new spaces. One way to put a space between the lines would be:

*cout << "5 / 5 = " << 5 / 5*

**<< "\n"**<< endl;This would display:

**5 + 5 = 10**

**5 - 5 = 0**

**5 * 5 = 25**

**5 / 5 = 1**

**5.0 / 6.0 = 0.833333**

**.**

**.**

**.**

The reason for this is that

**\n**character.

**\n = new line**

Couple of things to remember for \n is that it needed to be put between the " ". If you don't then you will get a compiler error. Also, it will go to a new line wherever you put it. For example:

*cout << "5 / 5 \n = " << 5 /5 << "\n" << endl;*

*cout << "5.0 / 6.0 = " << 5.0 / 6.0 << endl;*

Displays:

**5 / 5**

**= 1**

**5.0 / 6.0 = 0.833333**

I created 3 new lines in that one line of code. One after 5/5, another after the sum of 5/5 and another with endl;

It might seem like a no brainier, but it takes a while to get used to. The compiler does not care what you intend to do, it only does exactly what you say to do. I've created a few programs where the text was messed up because I forgot to add \n.

Arithmetic expressions:

The compiler also does not care what you type in between the quotes. I could have typed "This is a sandwich = " << 5 / 5 << endl; and it would have displayed

**This is a sandwich = 1**

Now after the quotes I had another funnel << and an arithmetic problem. You just need to type the math problem. You don't need any quotes. As a matter of fact you can't use them. Just type the problem in and the compiler will solve it for you and display it. The arithmetic characters are:

**+ add**

**- subtract**

*** multiply**

**/ divide**

**% modulus**

Using those will express a value.

**Example:**The expression 5 + 5 expresses the value 10.

The operators themselves are simple enough .Nothing surprising there except for %

That's a modulus. A modulus gives you the remainder when dividing two numbers. For example:

5 % 5 has a remainder of 0 so the answer is 0

9 % 5 has a remainder of 4 so the answer is 4

There are all kinds of ways I don't understand the modulus and how to use it so I'm not going to pretend to. I do know that when creating random numbers I need to use it, but random is a whole other type of beast. I'll blog about that in a later blog.

What I found most interesting about how C++ does math problems is that if you do not put a ".0" then it will not return any number after the decimal point. It will just return an integer. You need a .0 to get any kind of floating point. A floating point is a number with a fractional part. More on floats and integers later.

In the last example I am adding and multiplying the same numbers but in different orders. Just remember these order of operations

**multiplication, division and modulus have equal precedence.**They are evaluated first regardless of their position. In other words, they are evaluated before addition and subtraction.

To get around this you can use parentheses. Example (5 + 5) * 5 equals 50 because you first add 5 and 5. Then multiply it. Without the parenthesis you would multiply 5 and 5 and then add 5 which would be 30.

That does it for today.

Recap of what was learned:

- \n creates a new line
- Type the arithmetic problem out without quotes
**+ - * / %**are the arithmetic operators you use to get an expression- Expression is something that evaluates to a single value.
- To get a floating point expression you need to add .o to the number
- Order of operations. * / % expresses before + -
- Use parenthesis to get lower precedence operators to express a value first. Keep this in mind because it will become very important later on when learning more about C++

Same Rat-Time.

Same Rat-Channel