Unit 3 Session 2 (Click for link to problem statements)

Understand what the interviewer is asking for by using test cases and questions about the problem.

• What should my function return if the string is empty?
  • In this case, return an empty list.

Plan the solution with appropriate visualizations and pseudocode.

General Idea: First, create a map of each element -> its latest index. Then loop through the string, keeping track of the last appearance and current index. When they match, add the partition.

1) First, create a map of element -> latest index 2) Create an empty list, and set start and end to 0 3) For each index and char in the string: a) if last_index[char] is larger, update end b) if current index and end are equal i) add the partition to the list ii) move start to index+1 4) Return the partition list

def partition_label(s): last_index = {} for idx, char in enumerate(s): last_index[char] = idx partitions = [] start = 0 end = 0 for i, char in enumerate(s): end = max(end, last_index[char]) if i == end: partitions.append(end - start + 1) start = i + 1 return partitions