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Solution: Index Pairs of a String

Explore how to implement a trie to efficiently find all starting and ending index pairs of substrings in a text that match any word from a given list. This lesson teaches building and traversing a trie to optimize substring search and understand related time and space complexities.

Statement

Given a string text and an array of strings words, return a list of all index pairs [i, j] such that the substring text[i...j] is present in words.

Return the pairs [i, j] in sorted order, first by the value of i, and if two pairs have the same i, by the value of j.

Constraints:

  • 11 \leq text.length 100\leq 100

  • 11 \leq words.length 20\leq 20 ...