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{

        System.out.print (“Square of “ + number);
        System.out.println (“ = “ + number*number);
        ++number;
        }

        while (number <= 5);
        }}




















        The output of the DoWhileDemo program is the same as WhileDemo program. You might be wondering if both the
        while and do-while loops give the same output, what is the use of having two types of loop constructs. Well, consider
        the case when the variable number is initialized to 6.
        int number = 6;

        The while loop would first test whether number <= 5. Since 6 > 5, the condition is false and the loop body would not be
        entered and as a result nothing is displayed in the output window. However, in the case of the do-while loop, since the
        body of the loop is executed before the test condition, the square of 6 is printed (“Square of 6 = 36”), then, number is
        incremented to 7. Now the test for number >= 5 is made. Since 7 > 5, the condition is false and the loop is exited. To
        summarize, the do-while loop always executes at least once whereas the while loop executes zero or more times. The
        differences between while and do-while loop are as follows:
        Difference between while and do-while loop


                                While Loop                                   Do While Loop

              A while loop is an entry-controlled loop – it tests for  A do-while loop is an exit-controlled loop it tests
              a condition prior to running a block of code.  for a condition after running a block of code.

              A while loop runs zero or more times. Body of loop  A do-while loop runs once or more times but at
              may never be executed.                         least once.
              The variables in the test condition must be initialized  Body  of  loop  is  executed  at  least  once  It  is  not
              prior to entering the loop structure.          necessary  to  initialize  the  variables  in  the  test
                      While                                  condition prior to entering the loop structure.
                    (condition)                              do
                     {                                       {

                       Statements                            statements
                   }                                          }
                                                              while (condition);

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