fd

Author: dingjikerbo

README.md

@@ -388,5 +388,6 @@
 |684|[Redundant Connection](https://leetcode.com/problems/redundant-connection/)| [Java](leetcode/solution/src/RedundantConnection.java)|||
 |695|[Max Area of Island](https://leetcode.com/problems/max-area-of-island/)|[Java](leetcode/solution/src/MaxAreaOfIsland.java)|100||
 |771|[Jewels and Stones](https://leetcode.com/problems/jewels-and-stones/)|[Java](leetcode/solution/src/JewelsAndStones.java)|100||
+|819|[Most Common Word](https://leetcode.com/problems/most-common-word/)|[Java](leetcode/solution/src/MostCommonWord.java)|85||
 |904|[Fruit Into Baskets](https://leetcode.com/problems/fruit-into-baskets/)|[Java](leetcode/solution/src/FruitIntoBaskets.java)|90||
 |929|[Unique Email Addresses](https://leetcode.com/problems/unique-email-addresses/)|[Java](leetcode/solution/src/UniqueEmailAddresses.java)|90||

leetcode/solution/src/MostCommonWord.java

@@ -0,0 +1,44 @@
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.HashSet;
+
+public class MostCommonWord {
+
+    /**
+     * 要注意结尾的单词
+     */
+    public String mostCommonWord(String paragraph, String[] banned) {
+        HashMap<String, Integer> map = new HashMap<>();
+        HashSet<String> bannes = new HashSet<>(Arrays.asList(banned));
+
+        String result = null;
+        int count = 0;
+
+        boolean enterWord = false;
+        for (int i = 0, j = 0; j <= paragraph.length(); j++) {
+            char c = j < paragraph.length() ? paragraph.charAt(j) : '.';
+            if (Character.isAlphabetic(c)) {
+                if (!enterWord) {
+                    enterWord = true;
+                    i = j;
+                }
+            } else {
+                if (enterWord) {
+                    enterWord = false;
+                    String word = paragraph.substring(i, j).toLowerCase();
+                    if (!bannes.contains(word)) {
+                        int cnt = map.getOrDefault(word, 0) + 1;
+                        map.put(word, cnt);
+
+                        if (cnt > count) {
+                            count = cnt;
+                            result = word;
+                        }
+                    }
+                }
+            }
+        }
+
+        return result;
+    }
+}

leetcode/src/Main.java

@@ -4,34 +4,13 @@ public class Main {
 
     public static class Solution {
 
-        public List<Integer> topKFrequent(int[] nums, int k) {
-            HashMap<Integer, Integer> map = new HashMap<>();
-            int max = 0;
-            for (int n : nums) {
-                int cnt = map.getOrDefault(n, 0) + 1;
-                map.put(n, cnt);
-                max = Math.max(max, cnt);
-            }
-            List<Integer>[] lists = new ArrayList[max + 1];
-            for (Map.Entry<Integer, Integer> entry : map.entrySet()) {
-                int freq = entry.getValue();
-                if (lists[freq] == null) {
-                    lists[freq] = new ArrayList<>();
-                }
-                lists[freq].add(entry.getKey());
-            }
-            List<Integer> result = new ArrayList<>();
-            for (int i = max; i >= 0 && result.size() <= k; i--) {
-                if (lists[i] != null) {
-                    result.addAll(lists[i]);
-                }
-            }
-            return result.subList(0, k);
-        }
+
     }
 
 
     public static void main(String[] args) {
         Solution solution = new Solution();
+        String s = solution.mostCommonWord("Bob", new String[0]);
+        System.out.println(s);
     }
 }