Advertisement
Not a member of Pastebin yet?
Sign Up,
it unlocks many cool features!
- 1) 'Recursion on Non-Numerics' is to be revised for PSet, Problem 3.
- 2) fex: is in
- Exercise: is in
- 0.0/5.0 points (graded)
- ESTIMATED TIME TO COMPLETE: 18 minutes
- ---------------------------------------
- We can use the idea of bisection search to determine if a character is in a string, so long as the string is sorted in alphabetical order.
- First, test the middle character of a string against the character you're looking for (the "test character"). If they are the same, we are done - we've found the character we're looking for!
- If they're not the same, check if the test character is "smaller" than the middle character. If so, we need only consider the lower half of the string; otherwise, we only consider the upper half of the string. (Note that you can compare characters using Python's < function.)
- Implement the function isIn(char, aStr) which implements the above idea recursively to test if char is in aStr. char will be a single character and aStr will be a string that is in alphabetical order. The function should return a boolean value.
- As you design the function, think very carefully about what the base cases should be.
- -------------------------------------------------------------------------------------------------------------------------------------
- def isIn(char, aStr):
- '''
- char: a single character
- aStr: an alphabetized string
- returns: True if char is in aStr; False otherwise
- '''
- # Your code here
- ----------------
Advertisement
Add Comment
Please, Sign In to add comment
Advertisement