Given manywords,words[i]has weighti.

Design a classWordFilterthat supports one function,WordFilter.f(String prefix, String suffix). It will return the word with givenprefixandsuffixwith maximum weight. If no word exists, return -1.

Examples:

Input:

WordFilter(["apple"])
WordFilter.f("a", "e") // returns 0
WordFilter.f("b", "") // returns -1

Note:

1. words has length in range [1, 15000] .
2. For each test case, up to words.length queries WordFilter.f may be made.
3. words[i] has length in range [1, 10] .
4. prefix, suffix have lengths in range [0, 10] .
5. words[i] and prefix, suffix queries consist of lowercase letters only.

class WordFilter {
    HashMap<String, Integer> map = new HashMap<>();

    public WordFilter(String[] words) {
        for(int w = 0; w < words.length; w++){
            for(int i = 0; i <= 10 && i <= words[w].length(); i++){
                for(int j = 0; j <= 10 && j <= words[w].length(); j++){
                    map.put(words[w].substring(0, i) + "#" + words[w].substring(words[w].length()-j), w);
                }
            }
        }
    }

    public int f(String prefix, String suffix) {
        return (map.containsKey(prefix + "#" + suffix))? map.get(prefix + "#" + suffix) : -1;
    }
}

https://leetcode.com/problems/prefix-and-suffix-search/discuss/110044/Three-ways-to-solve-this-problem-in-Java