add: implement-trie-prefix-tree

Author: Yongseok-Choi-dev

implement-trie-prefix-tree/YoungSeok-Choi.java

@@ -0,0 +1,37 @@
+import java.util.HashMap;
+import java.util.Map;
+
+// Map으로 풀려버려서 당황..
+// 이진트리? 어떤식으로 풀어야 할지 자료구조 정하고 다시 풀어보기..
+class Trie {
+
+    Map<String, Boolean> tMap;
+
+    public Trie() {
+        this.tMap = new HashMap<>();
+    }
+    
+    public void insert(String word) {
+        this.tMap.put(word, true);
+    }
+    
+    public boolean search(String word) {
+        return this.tMap.containsKey(word);
+    }
+    
+    public boolean startsWith(String prefix) {
+        for(String key : this.tMap.keySet()) {
+            if(key.startsWith(prefix)) return true;
+        }
+
+        return false;
+    }
+}
+
+/**
+ * Your Trie object will be instantiated and called as such:
+ * Trie obj = new Trie();
+ * obj.insert(word);
+ * boolean param_2 = obj.search(word);
+ * boolean param_3 = obj.startsWith(prefix);
+ */