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C++ for new friends

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It is recommended to use an IDE Tutorial how to set it up HERE


Printing text to the screen

//Text that starts with "//" is ignored by the compiler 
//This is the library that allows you to use the "cout" and "endl" objects
#include <iostream>

//int main is where you will be writing your code example
//int main(){code goes here}
int main()
{
//std::cout is sending the text to your screen
//std::endl creates a new line
std::cout << "This text will appear on your sceen" << std::endl;
std::cout << "This text will appear on your sceen" << std::endl;
//Note: all statements must end with a ; such as above


return 0;
}





Using Data

#include <iostream>

int main()
{
//Numbers in C can be stored in variables
//Each type can store a different type of data
//For example an int is created by typing keyword int followed by a name, for this example bill
int bill; //this int can store Integers -3 -2 -1 0 1 2 3 etc
bool tom; //can store true or false
float jim; //can store a decimal
char tommy; //this takes characters such as 'x' or 'b'
//variables can be created with no data and set later in the program such as here
bill = 5;
tom = true;
jim = 1.5;
tommy = 'b';
//Just to prove everything works we will print these to the screen

std::cout<< "BIL "<<bill<<std::endl;
std::cout<< "TOM "<<tom<<std::endl;
std::cout<< "JIM "<<jim<<std::endl;
std::cout<< "TOMMY "<<tommy<<std::endl;

//note tom will appear as 1 or 0 depending on the true/false state 


return 0;
}




Conditions

#include <iostream>

int main()
{

int bill = 5;
char tommy = 'b';
//the if statement will look if the condition inside its brackets is true,
//if it is it will run the block of code below
//we are using the Equal to operator "==" to check if bill is equal to 5

//other operators include 
// !=	Not equal to
//>	Greater than
//<=	Less than or equal to
//>=	Greater than or equal to


if(bill == 5)
{
    tommy = 'X';
    //because bill is equal to 5 tommy will become X
}

if(bill == 6)
{
    tommy = 'Y';
    //because bill is not equal to 6 this code is ignored
}

std::cout<< "TOMMY "<<tommy<<std::endl;




return 0;
}





Loops

#include <iostream>

int main()
{

int bill = 5;
char tommy = 'b';
//like if, the while loop will run code if the condition is true
//unlike if, while loops do not stop until the condition becomes false
//below we used the Not equal to operator to check if bill is not equal to 0
while (bill != 0)
{
    std::cout<< "TOMMY "<<tommy<<std::endl;
    //while bill is not equal to 0 the loop will run and print out tommy
    bill--;
    //the loop will also reduce bill by 1  each time it runs 
    //thanks to the decrement operator "bill--" bill could also be Incremented with "bill++"
}
return 0;
}