How should I practice Lexicographically Last Substring?

Start by reading the full statement, solve the visible examples, then compare the pattern against related Roblox online assessment problems in FastPrep.

Is Lexicographically Last Substring associated with Roblox?

FastPrep tags this as a Roblox online assessment coding practice problem when the problem catalog has that company and stage context.

Lexicographically Last Substring

Roblox● HardNEW GRADOA

Learn

Problem statement

Consider every distinct nonempty contiguous substring of s, sorted in ascending lexicographic order. Return the last string in that order.

For this exercise, assume s contains lowercase English letters. Compare strings at their first differing letter; if one is a prefix of the other, the longer string is larger. Return an empty string when s is empty.

You only need to return the selected substring, not construct or return the full collection of substrings.

Function

lastSubstring(s: String) → String

Examples

Example 1

s = "abab"return = "bab"

Among the substrings starting with b, bab is larger than b. Every substring starting with a is smaller.

Example 2

s = "leetcode"return = "tcode"

t is the largest available first letter, and its full suffix is the largest substring starting there.

Example 3

s = "aaaa"return = "aaaa"

When strings share a prefix, the longer one is larger.

Constraints

0 <= s.length <= 5000.
Every character is a lowercase English letter.