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13.   Write the difference between a for loop and a while loop?
                    Ans.
                                       For Loop                               While Loop
                        In for loop, initialisation, test condition and   In while loop, initialisation, test condition
                        increment or decrement are in the same line.  and increment or decrement are written in
                                                                separate lines.
                        This  loop  executes a set of  statements  This loop is used to execute set of statements
                        repeatedly for a fixed number of times.  repeatedly based on the truth of a condition, if
                                                                the number of iterations is not known.

                     14.   State the difference between an entry-controlled loop and an exit-controlled loop.
                    Ans.           Entry control loop                       Exit control loop
                        Test condition is checked before the loop body  Test condition is checked after the loop body
                        gets executed.                          gets executed

                        Example for and while                   Example do-while

                     15.   Write one similarity and one difference between a while loop and a do-while loop.
                    Ans.              While loop                             Do-while loop
                                                           Similarity
                        This loop is used when the number of    This loop is used when the number of
                        iterations are not known.               iterations are not known.
                                                           Difference
                        If the test condition is false, then the loop will   The loop will execute at least once, even if
                        not execute. So, it is Entry control loop.  the test condition returns false. So, It is Exit
                                                                Control Loop
                     16.   What is the difference between a break statement and a continue statement when they occur in a loop?
                    Ans.
                                        break                                  continue
                        Used to exit from a loop.               Used to go to the next iteration in the loop
                           for(i=1;i<=5;i++)                       for(i=1;i<=5;i++)
                           {                                       {
                           if(i%2==0)                              if(i%2==0)
                           break;                                  continue;
                           System.out.print(i);                    System.out.print(i+ " ” );
                           }                                       }
                           Output will be : 1                      Output will be : 1 3 5
                     17.   Using a while loop, give an example of an infinite loop.
                    Ans.   Example:
                       int i;
                       i=1;
                       while(i>=1)
                       {
                       System.out.println(i);
                       }
                     18.   Using a for loop give an example of a null loop.
                    Ans.   Example:
                       for(int i=1;i<=1000;i++)
                       {     }


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