Add some code

leetcode/problems/cpp/replace-words.cpp

@@ -0,0 +1,70 @@
+#include "sstream"
+#include "string"
+#include "vector"
+
+using namespace std;
+
+class Trie {
+ public:
+   bool isEnd;
+   Trie* children[26];
+
+   Trie() {
+      isEnd = false;
+      for (int i = 0; i < 26; i++) {
+         children[i] = nullptr;
+      }
+      isEnd = false;
+   }
+};
+
+class Solution {
+ public:
+   Trie* root;
+   Solution() { root = new Trie(); }
+
+   void insert(string word) {
+      Trie* node = root;
+      for (char c : word) {
+         int i = c - 'a';
+         if (node->children[i] == nullptr) {
+            node->children[i] = new Trie();
+         }
+         node = node->children[i];
+      }
+      node->isEnd = true;
+   }
+
+   string search(string word) {
+      Trie* node = root;
+      string result;
+      for (char c : word) {
+         int i = c - 'a';
+         if (node->children[i] == nullptr) {
+            return word;
+         }
+         result += c;
+         if (node->children[i]->isEnd) {
+            return result;
+         }
+         node = node->children[i];
+      }
+      return word;
+   }
+
+   string replaceWords(vector<string>& dictionary, string sentence) {
+      for (string word : dictionary) {
+         insert(word);
+      }
+
+      stringstream ss(sentence);
+      string word, result;
+      while (ss >> word) {
+         if (!result.empty()) {
+            result += " ";
+         }
+         result += search(word);
+      }
+      return result;
+   }
+};

leetcode/problems/java/longest-palindrome.java

@@ -0,0 +1,24 @@
+import java.util.HashMap;
+import java.util.Map;
+
+class Solution {
+  public int longestPalindrome(String s) {
+    Map<Character, Integer> map = new HashMap<>();
+    for (char c : s.toCharArray()) {
+      map.put(c, map.getOrDefault(c, 0) + 1);
+    }
+
+    int result = 0;
+    boolean hasOdd = false;
+    for (int count : map.values()) {
+      if (count % 2 == 0) {
+        result += count;
+      } else {
+        result += count - 1;
+        hasOdd = true;
+      }
+    }
+
+    return hasOdd ? result + 1 : result;
+  }
+}