The document provides an introduction to basic C programming concepts like data types, variables, and printf statements. It explains that the main function is the starting point, and recommends declaring variables at the top for any values needed. Integer, float, and double data types are covered, along with how to declare, initialize, and print variables of each type using printf formatting codes. The last part provides a short sample program demonstrating these concepts.

2.  Before I explain any int main()
{
code to you, I int i;
would like you to int sum = 0;
execute your first for(i = 0; i<10; i++){
sum += i;
program by }
copying and
printf("Sum = %dn", sum);
pasting my code. //system("pause");
return 0;
}

3.  Locate the compile button and run
buttons in your program.
 You may alternatively find the compile
and run button that executes both at
once.
 You should notice a black box
appearing and disappearing very
quickly. That is because I have allowed
this code to execute without any pause
statements.

4.  Programs typically automatically close
once the final line of code is reached.
 The line system(“pause”); needs to be
added to “pause” the program in place
 The system pause should be placed right
before the return 0; line of any program.
Return 0 is typically used at the end of a
program to tell the computer the program
has ended.

5.  Code is normally presented omitting the
system("pause"); statement which
confuses new programmers. Always
make a mental note to add it in if you
are testing new code.

6.  When you place // before a line of
code, you comment the code out and
cause the compiler to skip over the
code.
 Now you can remove the // before the
system pause line in the example
program and run the program again to
see output. If all is correct, you should
see the output being Sum = 45.

8.  I want to draw your attention to the first line:
int main(){
 This is the beginning of your main function. The
function ends with the use of }.
 Any time you open a { bracket, you must close it with
a } bracket.
 As you can see with the main function, you can see
the entire main function enclosed within the { }
brackets.
 Additional code is allowed within the brackets. This
includes code that uses another set of { } as well.
 The last { bracket to be opened is the first one to be
closed when a } bracket is used.

9.  The main function is the starting point of
a program and where a compiler first
starts to execute your code.
 It is required in order to compile your
code, therefore it would be a good
practice to use the following template.

10. int main(){
//your new written code goes here
system("pause");
return 0;
}

11.  Our program is going to need a way to hold
our values
 These values are stored in different types of
variables.
 Integers, floats, and doubles are the main
“number” holders of a program.
 A variable in C programming must always be
declared at the top of the program right under
int main() { if you want to use the variable in
your program.
 Unlike some programming languages, you may
not locally declare a variable anywhere.

12.  An integer is a number only
representable in a whole number form.
 Integers: 1,2,3,4,5..
 Not Integers: 1.5, 1.7, 2.5, 3.9, 1003.4...
 Integer math is the calculation between
two integers. The math is calculated as
you would normally between any two
numbers except the decimal value is
dropped. Ex. 1+3=4, 1+.5=1 , 5/4 = 1

13.  Double and Float variables allow the use of
decimal numbers. A float has a smaller
default precision than a double.
 If you declare a float and then try to store
the number within the float into a double,
you may be transferring only part of the
number.
 A float allows at most about 7 decimal
places precision.
 A double allows at least 7 places.
 To accurately work beyond 7 decimals you
may require addition resources.

14.  I typically use only Doubles when working
with decimals and will work with only
Doubles within these tutorials.
 The math calculated with a double or
float does not use integer math. It would
be safe to assume the calculated
answer would be similar to the answer
given in a math class.

15.  An integer is declared by typing
int variablename;
 A float is declared by typing
float variablename;
 A double is declared by typing
double variablename;
 The variablename is changeable to
anything starting with a letter and
anything that has not been assigned to
a variable yet.

16.  Multiple variables of the same type are
declarable by adding a comma after
the first variable and then typing the
second.
 int one, two, three;

17.  The point of a variable is to eventually
hold data.
 The variable could be initialized
immediately with a value.
 int one = 1;
 double duck = 12.5;

18.  To print out the value a variable is holding
you use the printf statement
 printf(“The variable one = %d”, one);
 As shown above, the text you want printed
out is held within the quotation marks. A
%variabletype is added to signal to the
computer you want to print out a variable.
 int -> %d float -> %fl double -> %lf
 After the comma, you list the variables in
order that match up with the %variables

19.  A double could be printed out but it may
contain too many decimal places.
 Limit a double by using %.#lf for the
number of decimal places you want to
be printed out.
 The key “n” to a computer is
interpreted as a line break.
 When used in a printf statement, it will
add a line break into the output.

20. int main(){
int one = 5.5;
float two = 7.5;
double three = 10.5;
printf("One equals: %d n", one);
printf("Two equals: %f n", two);
printf("Three equals: %lf n ", three);
three = 15;
printf("Three equals: %lf ", three);
system("pause");
return 0;
}

21.  Programming Template
 Integers, Floats, and Doubles
 Printf statements