[attachment=10978]
Variables and Assignments
 Variables are like small blackboards
 We can write a number on them
 We can change the number
 We can erase the number
 C++ variables are names for memory locations
 We can write a value in them
 We can change the value stored there
 We cannot erase the memory location
 Some value is always there
Identifiers
 Variables names are called identifiers
 Choosing variable names
 Use meaningful names that represent data to
be stored
 First character must be
 a letter
 the underscore character
 Remaining characters must be
 letters
 numbers
 underscore character
Keywords
 Keywords (also called reserved words)
 Are used by the C++ language
 Must be used as they are defined in
the programming language
 Cannot be used as identifiers
Declaring Variables
 Before use, variables must be declared
 Tells the compiler the type of data to store

Examples: int number_of_bars;
double one_weight, total_weight;
 int is an abbreviation for integer.
 could store 3, 102, 3211, -456, etc.
 number_of_bars is of type integer
 double represents numbers with a fractional
component
 could store 1.34, 4.0, -345.6, etc.
 one_weight and total_weight are both of type double
 Two locations for variable declarations
 Immediately prior to use

int main()
{
…
int sum;
sum = score1 + score 2;
…
return 0;
}
 At the beginning

int main()
{
int sum;
…
sum = score1 + score2;
…
return 0;
}
 Declaration syntax:
 Type_name Variable_1 , Variable_2, . . . ;
 Declaration Examples:
 double average, m_score, total_score;
 double moon_distance;
 int age, num_students;
 int cars_waiting;
Assignment Statements
 An assignment statement changes the value of a variable
 total_weight = one_weight + number_of_bars;
 total_weight is set to the sum one_weight + number_of_bars
 Assignment statements end with a semi-colon
 The single variable to be changed is always on the left
of the assignment operator ‘=‘
 On the right of the assignment operator can be
 Constants -- age = 21;
 Variables -- my_cost = your_cost;
 Expressions -- circumference = diameter * 3.14159;

Oh Great for me :thanks

C++ is an object oriented language. This language is some what like c language. If you want to learn more about c++ you can refer some basic level books like balagurusami, complete reference.

C + + is a multi-paradigm language. This allows developers to choose the programming style, suitable for the task at hand. I know English. Equally important, on the other players know it very well. C + + is a very broad language of the huge user base.