Classic word break problem dressed up with a 'suffix' label, which threw me for a second because I kept thinking it meant something about actual string suffixes.
Start by clarifying the problem constraints (e.g., word list size, target length, character set) and discuss the brute-force approach. Then, propose an efficient solution using dynamic programming (DP) where dp[i] indicates if the prefix of length i can be segmented. Optimize by iterating over words and checking if they match the substring ending at i, or by using a trie for faster lookups.
Pro tip: Mention that you can preprocess the word list to find the maximum word length and only check substrings up to that length, significantly reducing time complexity. Also, consider using a set for O(1) word lookups.
Ask about input sizes, character set, and whether empty strings or empty word lists are possible. This shows attention to detail and helps choose the right algorithm.
Explain that a naive recursive approach would try all possible segmentations, leading to exponential time. This sets the stage for a more optimal solution.
Define dp[i] as whether the prefix of length i can be segmented. Initialize dp[0] = true. For each i from 1 to n, check all words: if dp[i - len(word)] is true and the substring matches, set dp[i] = true.
To avoid checking all words for each position, build a trie of the word list and traverse it from each i where dp[i] is true, or limit substring checks to the maximum word length.
State time complexity: O(n * m * L) for DP with word list, where n is target length, m is number of words, L is average word length; with trie, O(n * L). Space complexity O(n). Walk through an example to verify.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.