Page 75 - TP_Modular_V2.1_Class5
P. 75

USE OF LOOP BLOCKS

                 All the programs or projects developed till now run only once. If you want to run
                 a set of statements more than once, you will either run the code again or write
                 the script again. In Scratch, we can save our time and effort by repeating the code

                 without  writing  the  program  again  or  writing  the  script  again.  The  automatic
                 running of a set of instructions more than once is called looping. The blocks for
                 looping are given in the Control category.

                 The repeat block is used to run a set of instructions for a specified
                 number of times.


                              The repeat until block is used to run a set of instructions till a condition
                              is satisfied.

                 The forever block is used to run a set of instructions continuously
                 until stopped. The instructions inside this block will be executed in a
                 loop until the Stop button            is clicked by the user.

                 The Repeat and Repeat Until blocks can be used to display the table of a number
                 input by the user. The script for the sprite can be like this (using the Repeat Until

                 block). Following is the script for displaying table of a number:



















                 The output of the program will be similar to this.















                 You can also use the forever and repeat blocks with if...then block.

                 Let us make a small script. Change the sprite to butterfly and change the backdrop
                 to flowers.



                                                                                 Creating a Game in Scratch       73
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