[Tutor] How to solve this problem in python?

Ratna Banjara mast.ratna at gmail.com
Sun Apr 24 12:32:32 CEST 2011

 Write a function named countRepresentations that returns the number
of ways that an amount of money in rupees can be represented as rupee
notes. For this problem we only use  rupee notes in denominations of
1, 2, 5, 10 and 20 rupee notes.

The signature of the function is:
   def countRepresentations(int numRupees)

For example, countRepresentations(12) should return 15 because 12
rupees can be represented in the following 15 ways.
  1. 12 one rupee notes
  2. 1 two rupee note plus 10 one rupee notes
  3. 2 two rupee notes plus 8 one rupee notes
  4. 3 two rupee notes plus 6 one rupee notes
  5. 4 two rupee notes plus 4 one rupee notes
  6. 5 two rupee notes plus 2 one rupee notes
  7. 6 two rupee notes
  8. 1 five rupee note plus 7 one rupee notes
  9. 1 five rupee note, 1 two rupee note and 5 one rupee notes
  10. 1 five rupee note, 2 two rupee notes and 3 one rupee notes
  11. 1 five rupee note, 3 two notes and 1 one rupee note
  12. 2 five rupee notes and 2 one rupee notes
  13. 2 five rupee notes and 1 two rupee note
  14. 1 ten rupee note and 2 one rupee notes
  15. 1 ten rupee note and 1 two rupee note

Hint: Use a nested loop that looks like this. Please fill in the
blanks intelligently, i.e. minimize the number of times that the if
statement is executed.
for (int rupee20=0; rupee20<=__; rupee20++)
   for (int rupee10=0; rupee10<=__; rupee10++)
      for (int rupee5=0; rupee5<=__; rupee5++)
         for (int rupee2=0; rupee2<=__; rupee2++)
            for (int rupee1=0;  rupee1<=__; rupee1++)
                if (___)

Ratna P Banjara

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