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Problem 17: Write an algorithm to delete any word from a sentence.
              Step 1:  Start.
              Step 2:  Accept sentence in variable sen and delete word in del_word.

              Step 3:  Add space at the end of sen.
              Step 4:  Initialise variables word and new_sentence to null.
              Step 5:  Initialise length as sentence_length.

              Step 6:  Initialise i to 0.
              Step 7:  Repeat Step 8 to Step 14 while i < length.
              Step 8:  Extract each character in ch.
              Step 9:  If ch is equal to space then go to Step 10 else go to Step 13.

              Step 10: If word = del_word then go to Step 12.
              Step 11: Add word to new_sentence and then add space to new_sentence.
              Step 12: Initialise word to null, go to Step 14.

              Step 13: Add ch to word.
              Step 14: Increment i by 1.
              Step 15: Display new_sentence.
              Step 16: Stop.


              14.5.7 Recursive Algorithms
                                                                        b
              Problem 18: Write a recursive algorithm to find power(a, b) or a .
              Step 1:  Start.
              Step 2:  Accept a and b
              Step 3:  If b = 1 then return 1, else go to Step 3.

              Step 4:  Return a x power(a, b-1).
              Step 5:  Stop.
              Problem 19: Write a recursive algorithm to find the sum of the digits of a number sumofdigit(num).

              Step 1:  Start.
              Step 2:  If num = 0 then return 0, else go to Step 3.
              Step 3:  Return num % 10 + sumofdigit(num/10).
              Step 4:  Stop.



                              Let’s Revisit


                     ♦ An algorithm is a set of well-defined finite steps or rules to be followed to solve any problem.

                     ♦ Pseudocode is a representation of an algorithm in any standard human readable language and mathematical notations.
                     ♦ Flowchart is a pictorial representation of an algorithm using standard symbols.
                     ♦ Big O notation is the measurement of growth rate of an algorithm with increase in its input size.
                     ♦ A good algorithm should have various properties like accuracy, finiteness, input, output, language independence, and
                   effectiveness.



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