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08


                                                                    STATEMENTS AND SCOPE
















                        Learning Objectives



                   8.1  Different Types of Statements                8.2  Scope of Variables
                   8.3  Compound Statements                          8.4  Control Statements
                   8.5  Mathematical Functions



              A set of instructions written in the correct order in any programming language performs a specific function.
              These instructions are basically a set of commands which directs the compiler to carry out the desired task. These
              instructions are called “Statements”. In this chapter, we shall deal with all types of statements and their uses in Java
              programming.

                   8.1 DIFFERENT TYPES OF STATEMENTS
              There are three types of statements in Java which are as follows:
              •  Expression Statements

              •  Declaration Statements
              •  Control Statements
              Let us discuss them one by one:

              8.1.1 Expression Statements
              These statements consist of an expression that calculates certain equations and produces a result. They may involve
              calculations such as a+b, 4*(4%2), etc. or expressions that modify the value of a variable in a program such as a++, --b
              or even int add=a+b;


              8.1.2 Declaration Statements
              These statements are used to declare what type of data the variables or constants will contain.

              For example,
                  int sum; double pi; boolean flag; char ch;
                  int sum=0; double pi=3.142; boolean flag=true; char ch='a';
              8.1.3 Control Statements
              These statements are used to decide in which direction the program will execute. There are mainly four types of control
              statements. They are—Sequential statements, Conditional statements, Iterative statements and Jump statements.



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