refactor 642

Author: fishercoder1534

src/main/java/com/fishercoder/solutions/_642.java

@@ -7,61 +7,6 @@
 import java.util.List;
 import java.util.Map;
 
-/**
- * 642. Design Search Autocomplete System
- *
- * Design a search autocomplete system for a search engine. Users may input a sentence (at least one word and end with a special character '#'). For each character they type except '#', you need to return the top 3 historical hot sentences that have prefix the same as the part of sentence already typed. Here are the specific rules:
-
- The hot degree for a sentence is defined as the number of times a user typed the exactly same sentence before.
- The returned top 3 hot sentences should be sorted by hot degree (The first is the hottest one). If several sentences have the same degree of hot, you need to use ASCII-code order (smaller one appears first).
- If less than 3 hot sentences exist, then just return as many as you can.
- When the input is a special character, it means the sentence ends, and in this case, you need to return an empty list.
- Your job is to implement the following functions:
-
- The constructor function:
-
- AutocompleteSystem(String[] sentences, int[] times): This is the constructor. The input is historical data. Sentences is a string array consists of previously typed sentences. Times is the corresponding times a sentence has been typed. Your system should record these historical data.
-
- Now, the user wants to input a new sentence. The following function will provide the next character the user types:
-
- List<String> input(char c): The input c is the next character typed by the user. The character will only be lower-case letters ('a' to 'z'), blank space (' ') or a special character ('#'). Also, the previously typed sentence should be recorded in your system. The output will be the top 3 historical hot sentences that have prefix the same as the part of sentence already typed.
-
-
- Example:
- Operation: AutocompleteSystem(["i love you", "island","ironman", "i love leetcode"], [5,3,2,2])
- The system have already tracked down the following sentences and their corresponding times:
- "i love you" : 5 times
- "island" : 3 times
- "ironman" : 2 times
- "i love leetcode" : 2 times
- Now, the user begins another search:
-
- Operation: input('i')
- Output: ["i love you", "island","i love leetcode"]
- Explanation:
- There are four sentences that have prefix "i". Among them, "ironman" and "i love leetcode" have same hot degree. Since ' ' has ASCII code 32 and 'r' has ASCII code 114, "i love leetcode" should be in front of "ironman". Also we only need to output top 3 hot sentences, so "ironman" will be ignored.
-
- Operation: input(' ')
- Output: ["i love you","i love leetcode"]
- Explanation:
- There are only two sentences that have prefix "i ".
-
- Operation: input('a')
- Output: []
- Explanation:
- There are no sentences that have prefix "i a".
-
- Operation: input('#')
- Output: []
- Explanation:
- The user finished the input, the sentence "i a" should be saved as a historical sentence in system. And the following input will be counted as a new search.
-
- Note:
- The input sentence will always start with a letter and end with '#', and only one blank space will exist between two words.
- The number of complete sentences that to be searched won't exceed 100. The length of each sentence including those in the historical data won't exceed 100.
- Please use double-quote instead of single-quote when you write test cases even for a character input.
- Please remember to RESET your class variables declared in class AutocompleteSystem, as static/class variables are persisted across multiple test cases. Please see here for more details.
- */
 public class _642 {
     public static class Solution1 {