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THE POWERFUL LOOPING

A software clock

FOR I = 0 TO 24     ' hour
   FOR J = 0 TO 60    "minute
       FOR K = 0 TO 60    'second
        one second delay
         PRINT I ":"J":"K     'time
        NEXT K
    NEXT J
NEXT I

    The above small program displays time.

     The I loop executes for 24 times to indicate the hour.  For each I loop, J loop executes for 60 times (minutes).  For each J loop, K loop is iterated 60 times (seconds).

    So the command 'print' (display) is executed 86400 times in 24 hours.

    So the loop iterates itself untiringly.  The loops can be nested to create complex process.  But they should be handled carefully and stopped properly.  Else they will slip into infinite iterations causing programming nightmares.

     Mostly computer processes are repeated ones and the 'loop' plays the main role.  Example: to print the exam results of 1000000 students.

A fractal is generated by repeating the pattern


   The exponentiation is repeated multiplication; the multiplication is repeated addition.  Addition of the numbers is the repeated addition of 1 s and 0 s.

     Example:   3 ^3 = 3*3*3
3*3 = 3+3+3
3+3 = 11+11 (binary)

    So the computer breaks down complex task into smaller repeated tasks and executes neatly using the 'loops'. 

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