[ICE_]

before I begin i'd like to say this is 100% MINE i am just transferring from SF

If statements
an if statement is a comparison statement. the if statement is seen in 3 different ways:

if (condition){ codeblock}
else if(condition){codeblock}
else{codeblock}


The if statement is always the first type to be used, then the else if, then the else.
When comparing two items in an if statment, such as 'x' and 'y' one should use the '==' and '!=' operators:

== -- compares the 2, if x is_Exactly_equal_to y
!= -- not equal to, if x is_not_equal_to y


An example of the if statement would be:

Code:

#include <iostream>

using namespace std;

int main()
{
  int five = 5;

  if(five > 5){// if 5 is greater than 5
  cout <<"high";
  }
  else if (five == 5){// if 5 equals 5
   cout<<"correct";
  }
  else{// if the above 23
      cout << "too low"
  }

}

Another example using strings could be:

Code:

#include <iostream>

using namespace std;

int main()
{
string password;
cout <<"enter password: ";
cin >> password;

if (password != "passss"){
cout << "access denied.\n";
}
else if (password == "passss"){
cout << "access granted."\n;
}

}

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Different functions

The main() function is not the only function that can be made in c++, in-fact, functions can easily be made by just writing:

Code:

void FUNCTION_NAME(){

}

You can also make integer functions, string functions, etc.

In addition to this, functions can take in variables such as strings or ints like so:

Code:

void FUNCTION_NAME(string name,int age){

}

One use for this would be:

Code:

#include <iostream>

using namespace std;
int add(int a, int b){
return a + b;//this will just return the value of the sum of integers a and b
}
int main()
{
   int a;
   int b;
cout <<"enter a number: ";
cin >> a;
cout <<"enter another number: ";
cin >> b;
cout<< "the sum of the two numbers you entered is: "<<add(a,b)<<'\n';

}

As you can see, using this has cut out lines of code from the calculator we made in part 1.
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Loops

In c++, just as in any other language, there are multiple types of loop that will loop through lines of code and repeat them until a 'trigger' is set off. Some kinds of loops are:

while -- while(conditional){code block}
for - for(int i = NUMBER; i is < OR > OR = ETC. NUMBER; i++ (add 1 to i each time)/i--(subtract 1 to i each time)
do-while-- do{codeblock}while(conditional)


Examples of these loops are:

while loop:

Code:

#include <iostream>

using namespace std;

int main()
{
   int i = 0;
   while(i < 10){
   cout << i<<endl;
   i++;
   }

}

This will print out 1-10
-----------------------------
For loop

Code:

#include <iostream>

using namespace std;

int main()
{
   for(int i = 0; i < 10; i++){
   cout<<i<<endl;
   }
}

Will print out 1-10
-----------------------------
do-while loop

Code:

#include <iostream>

using namespace std;

int main()
{
   int i = 0;
  do{
  cout<<i<<endl;
  i++;
  }while(i<10);

}

Will print out 1-10
______________________________________
Advanced Calculator

Code:

#include <iostream>

using namespace std;
int divide(int g, int h)
{
   return g / h;
}
int multiply(int e, int f)
{
   return e * f;
}
int subtract(int c, int d)
{
   return c - d;
}

int add(int a, int b)
{
   return a + b;
}

int main()
{
   string choice;
   cout << "would you like to add,subtrace,multiply,or divide?(a,s,m,d): ";
   cin >> choice;

   if(choice == "a"){
   int a,b;//creates 2 integers
   cout <<"enter first number: ";
   cin >> a;
   cout <<"enter second number: ";
   cin >> b;
   cout <<"answer: "<<add(a,b)<<endl;
   }
   else if(choice == "s"){
   int c,d;//creates 2 integers
   cout <<"enter first number: ";
   cin >> c;
   cout <<"enter second number: ";
   cin >> d;
   cout <<"answer: "<<subtract(c,d)<<endl;
   }
   else if(choice == "m"){
   int e,f;//creates 2 integers
   cout <<"enter first number: ";
   cin >> e;
   cout <<"enter second number: ";
   cin >> f;
   cout <<"answer: "<<multiply(e,f)<<endl;
   }
    else if(choice == "d"){
   int g,h;//creates 2 integers
   cout <<"enter first number: ";
   cin >> g;
   cout <<"enter second number: ";
   cin >> h;
   cout <<"answer: "<<divide(g,h)<<endl;
   }
   else{
   cout<<"unknown answer: shutting off.\n";
   }

}

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I hope you guys liked this tutorial!