C++ for new friends
It is recommended to use an IDE, for a tutorial on how to set one up click HERE
Other great resource for learning C++ from the ground up.
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
// note: 'std::' means you are using a member of the namespace 'std'
// more on that later.
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 (or 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)
{
//while bill is not equal to 0 the loop will run and print out tommy
std::cout<< "TOMMY "<<tommy<<std::endl;
//the loop will also reduce bill by 1 each time it runs:
bill--;
//thanks to the decrement operator "bill--" bill could also be Incremented with "bill++"
}
return 0;
}
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