Questions for 18-Aug and 25-Aug session. This week and next we will review strings, permutations and combinations. Want to join us? Head over to SDE Skills Meetup (http://www.meetup.com/SDE-Skills-Seattle/events/232467359/) to RVSP
- Given a String of N chars
- Permutations: Generate all arrangements of R letters
- Combinations: Generates all selections of R letters
- Given a Symbol set of N chars
- Perm with Replacement: Generate all arrangements of R length with replacement
- isRearrangement: Given two strings, validate if they are rearrangements of each other.
- InferSymbolSet: Given an array of strings, find the symbol set that can be used to generate these strings.
- InferMasterString: Given an array of strings, create the shortest “master string” such that all the strings in the array are arrangements of.
- De Bruijn Sequence: Generate and print the “De Bruijn sequence” of B(Base, Length). Output for B(2,3) is 00010111 or 11101000
- Longest Alternating Subsequence: Given an array of ints, Find the longest alternating subsequence. Alternating inc, dec, inc or dec, inc dec.
- Find Close Species: You are given the genetic sequence of all the species of a planet (in the form of nucleobases AGCT). Two species are considered “close” if the order in which these nucleobases occur in their generic sequence matches more than 50% of the smaller sequence.
S1 is “not close” to S2, nothing in common
S1 is “close” to S3, as 5 A’s appear in order (not necessarily together) in S3.
S2 is “close” to S3, as 5 C’s appear in order in S3
- Given a string, find the longest palindrome you can make if you are permitted to rearrange the letters in the String. How will you make this happen with minimum number of swap operations?