Challenge Lesson 8 Source Code

List of videos 
Challenge 1

First Challenge

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Solution 1

#include <iostream>
using namespace std;

int main()
{
	double base = 0;
	double height = 0;
	double Rectangle_Area = 0;
	double Triangle_Area = 0;

	cout << "Type in a length of a rectangle: ";
	cin >> base;
	cout << "Type in a height of a rectangle: ";
	cin >> height;
	Rectangle_Area = base*height;

	cout << "Type in a length of a triangle: ";
	cin >> base;
	cout << "Type in a height of a triangle: ";
	cin >> height;
	Triangle_Area = base*height/2;

	cout << endl << "Area of Rectangle: " << Rectangle_Area << endl
	<< "Area of Triangle: " << Triangle_Area << endl <<
	"Sum of area: " << Rectangle_Area + Triangle_Area << endl;
	system("pause");
}



Solution 2

#include <iostream>
using namespace std;

int main()
{
	double Rectbase = 0;
	double Rectheight = 0;
	double Tribase = 0;
	double Triheight = 0;

	cout << "Type in a length of a rectangle: ";
	cin >> Rectbase;
	cout << "Type in a height of a rectangle: ";
	cin >> Rectheight;

	cout << "Type in a length of a triangle: ";
	cin >> Tribase;
	cout << "Type in a height of a triangle: ";
	cin >> Triheight;

	cout << endl;
	cout << "Area of Rectangle: " << Rectbase*Rectheight 	<< endl;
	cout << "Area of Triangle: " << Tribase*Triheight/2 	<< endl;
	cout << "Sum of area: " << Rectbase*Rectheight+Tribase*Triheight/2
	<< endl;
	system("pause");
}

Lesson 11 Source Code

List of videos 
Lesson 11 Video

To get the full benefit of the lesson, watch the video

Lesson 11: Introduction to the if statement

NOTE: for a fast copy, follow these steps in order:

Click anywhere in a text box below (result will be a blinking vertical line in the text box)
Hit ctrl + A on the key board (the "ctrl + A" means hit Ctrl and A at the same time)
(The result should be that all the text inside the text box lights up in blue)
Hit Ctrl + C (Nothing significantly happens that is visible) and now its copied to the clipboard and your ready to paste it anywhere 

you wish



if statements


The if statement will only take bool parameter (value inside the paranthesis).
The if statement will either skip or execute the following program statement depending on the boolean value of the if statement.
Run both of these pieces of code. refer to the video for the detailed explanation.
#include <iostream>
using namespace std;

int main()
{
 if(true)
 cout << "my name is iam4eversmart88" << endl;
 cout << "what is your name";
 cin.get();
 return 0;
}

#include <iostream>
using namespace std;

int main()
{
 if(false)
 cout << "my name is iam4eversmart88" << endl;
 cout << "what is your name";
 cin.get();
 return 0;
}


the if statement can also refer to code blocks (code inside curly braces) to skip multiple lines of code.
#include <iostream>
using namespace std;

int main()
{
 if(false)
 {
  cout << "my name is iam4eversmart88" << endl;
  cout << "what is your name";
 }
 cin.get();
 return 0;
}


you can input variables into th if parameter.
You can also put in int, double, char, etc types but don't forget the rules of the boolean values that aren't true or false.
#include <iostream>
using namespace std;

int main()
{
 bool Boolean=true;
 if(Boolean)
 {
  cout << "my name is iam4eversmart88" << endl;
  cout << "what is your name";
 }
 cin.get();
 return 0;
}


Here are slightly more practical examples that might help you see why if statements are useful
#include <iostream>
using namespace std;

int main()
{
 bool Boolean=true;
 float x=6.1;
 if(Boolean)
 {
  x=999.1;
 }
 cout << x;
 cin.get();
 return 0;
}

#include <iostream>
using namespace std;

int main()
{
 bool Boolean=false;
 float x=6.1;
 if(Boolean)
 {
  x=999.1;
 }
 cout << x;
 cin.get();
 return 0;
}

Lesson 20 Source Code

List of videos 
Lesson 20 Video

Lesson 20: The while loop part 3: break statement

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you wish


A prime number algorithm


Here is an infinite loop that we have encountered in the past. This is a bug that can be very difficult to find.
#include <iostream>
using namespace std;

int main()
{
 int count=0;
 while(true)
 {
  cout << count << endl;
  count++;
 }
 system("pause");
 return 0;
}


We can add a condition in the while loop parameter that changes each time by using a counting variable.
#include <iostream>
using namespace std;

int main()
{
 int count=0;
 while(count < 10)
 {
  cout << count << endl;
  count++;
 }
 system("pause");
 return 0;
}



Prime number algorithm


In this program, you will enter a positive Integer value for a, and it will tell you if that number is prime or not
#include <iostream>
using namespace std;

int main()
{
 int a, n=2;

 cout << "Enter a number for a: ";
 cin >> a;
 while(n<=a)
 {
  if(n==a)
  {
   cout << a << " is Prime!\n";
   break;
  }
  if(a%n==0)
  {
   cout << a << " is Divisible by" << n << endl;
   break;
  }
  n=n+1;
 }
 system("pause");
 return 0;
}


Here is the algorithm that prints off many prime numbers to the screen. Just enter an Integer value for x and it will print off that 

many random numbers.
#include <iostream>
using namespace std;

int main()
{
 int a=2, n=2, x;

 cout << "Enter a number for x: ";
 cin >> x;
 while(a<=x)
 {
  while(n<=a)
  {
   if(n==a)
   {
    cout << a << " is Prime!\n";
    break;
   }
   if(a%n==0)
   {
    cout << a << " is Divisible by" << n << endl;
    break;
   }
   n=n+1;
  }
  a++;
  n=2;
 }
 system("pause");
 return 0;
}

from 2 to x is the range of values that will be printed. a is the variable we are testing to see if its prime or not. n is the divisor 

that determines if it really is prime or not.

Notice that when you escape from the second while loop, n has to be set back equal to 2 because in the we need to start off dividing the 

next number by 2 just as we have been doing for the first number.

Lesson 16 Source Code

List of videos 
Lesson 16 Video

Lesson 16: The while loop

NOTE: for a fast copy, follow these steps in order:

Click anywhere in a text box below (result will be a blinking vertical line in the text box)
Hit ctrl + A on the key board (the "ctrl + A" means hit Ctrl and A at the same time)
(The result should be that all the text inside the text box lights up in blue)
Hit Ctrl + C (Nothing significantly happens that is visible) and now its copied to the clipboard and your ready to paste it anywhere you wish


beginning while loop examples

This will print my name 5 times to the screen
#include <iostream>
using namespace std;

int main()
{
 int a=0;
 while(a<5)
 {
  cout << "iam4eversmart88" << endl;
  a = a + 1;
 }
 cin.get();
 return 0;
}


This program code will count from 0 to 24 
#include <iostream>
using namespace std;

int main()
{
 int a=0;
 while(a<25)
 {
  cout << a << endl;
  a = a + 1;
 }
 cin.get();
 return 0;
}


This program will NEVER END. This is a common bug called the infinite loop 
#include <iostream>
using namespace std;

int main()
{
 int a=0;
 while(a<=500)
 {
  cout << a << endl;
  a = 2*a;
 }
 cin.get();
 return 0;
}


This program will double the value of "a" and print it out to the screen until a is greater than 500
(NOTE: There is only 1 difference compared to the program above this one)
#include <iostream>
using namespace std;

int main()
{
 int a=1;
 while(a<=500)
 {
  cout << a << endl;
  a = 2*a;
 }
 cin.get();
 return 0;
}


This program will dived a by 2 each time until a is 0;
#include <iostream>
using namespace std;

int main()
{
 int a=1000000;
 while(a>0)
 {
  cout << a << endl;
  a = a/2;
 }
 cin.get();
 return 0;
}

Lesson 10 Source Code

List of videos 
Lesson 10 Video

To get the full benefit of the lesson, watch the video

Lesson 10: The bool (Boolean) type

NOTE: for a fast copy, follow these steps in order:

Click anywhere in a text box below (result will be a blinking vertical line in the text box)
Hit ctrl + A on the key board (the "ctrl + A" means hit Ctrl and A at the same time)
(The result should be that all the text inside the text box lights up in blue)
Hit Ctrl + C (Nothing significantly happens that is visible) and now its copied to the clipboard and your ready to paste it anywhere 

you wish



small char programs


Boolean types can hold either true or false
#include <iostream>
using namespace std;

int main()
{
 bool smart=true;
 cout << smart;
 cin.get();
 return 0;
}

#include <iostream>
using namespace std;

int main()
{
 bool smart=false;
 cout << smart;
 cin.get();
 return 0;
}


If the value is set a number that is not equal to 0 the boolean value will be set to true
#include <iostream>
using namespace std;

int main()
{
 bool smart=13;
 cout << smart;
 cin.get();
 return 0;
}


If the value is set to 0, the boolean value will be considered false.
#include <iostream>
using namespace std;

int main()
{
 bool smart=0;
 cout << smart;
 cin.get();
 return 0;
}

Lesson 9 Source Code

List of videos 
Lesson 9 Video

To get the full benefit of the lesson, watch the video

Lesson 9: The char type

NOTE: for a fast copy, follow these steps in order:

Click anywhere in a text box below (result will be a blinking vertical line in the text box)
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Hit Ctrl + C (Nothing significantly happens that is visible) and now its copied to the clipboard and your ready to paste it anywhere 

you wish



small char programs


The char can only hold ONE character. that character has to be inside single quotations.
#include <iostream>
using namespace std;

int main()
{
 char character = 't';

 cout << character;

 cin.get();
 return 0;
}


Initializing and assigning multiple variables
#include <iostream>
using namespace std;

int main()
{
 char character = 't', ch2='~', ch3='|';

 cout << character << endl << ch2 << endl << ch3;

 cin.get();
 return 0;
}

Lesson 8 Source Code

List of videos 
Lesson 8 Video

To get the full benefit of the lesson, watch the video

Lesson 8: The cin statement

NOTE: for a fast copy, follow these steps in order:

Click anywhere in a text box below (result will be a blinking vertical line in the text box)
Hit ctrl + A on the key board (the "ctrl + A" means hit Ctrl and A at the same time)
(The result should be that all the text inside the text box lights up in blue)
Hit Ctrl + C (Nothing significantly happens that is visible) and now its copied to the clipboard and your ready to paste it anywhere 

you wish



The cin statement


The cin statement allows the user to enter a value for x in this example
#include <iostream>
using namespace std;

int main()
{
 int x=6;
 cout << "Enter an integer value: ";
 cin >> x;
 cout << "you have entered " << x << endl;
 system("pause");
 return 0;
}

notice that the cin.get() statement is replaced by the system("pause") because the cin.get() will not work once cin has been called. (i 

don't know why that is the case)

Here is another example. Computers don't like to divide by zero, you can try to input 0 for y to see what happens or you can also find 

out what happens by watching the video.
#include <iostream>
using namespace std;

int main()
{
 int x;
 int y;
 cout << "Enter a dividend: ";
 cin >> x;
 cout << "Enter a divisor: ";
 cin >> y;
 cout << "The quotient is " << x/y << " with a remainder of " << x%y << endl;
 system("pause");
 return 0;
}