Merge pull request #521 from AlgorithmWithGod/khj20006

[20250722] BOJ / P5 / 이진 검색 트리 / 권혁준

Author: ShinHeeEul

khj20006/202507/22 BOJ P5 이진 검색 트리.md

@@ -0,0 +1,105 @@
+```java
+import java.util.*;
+import java.io.*;
+
+class IOController {
+    BufferedReader br;
+    BufferedWriter bw;
+    StringTokenizer st;
+
+    public IOController() {
+        br = new BufferedReader(new InputStreamReader(System.in));
+        bw = new BufferedWriter(new OutputStreamWriter(System.out));
+        st = new StringTokenizer("");
+    }
+
+    String nextLine() throws Exception {
+        String line = br.readLine();
+        st = new StringTokenizer(line);
+        return line;
+    }
+
+    String nextToken() throws Exception {
+        while (!st.hasMoreTokens()) nextLine();
+        return st.nextToken();
+    }
+
+    int nextInt() throws Exception {
+        return Integer.parseInt(nextToken());
+    }
+
+    long nextLong() throws Exception {
+        return Long.parseLong(nextToken());
+    }
+
+    double nextDouble() throws Exception {
+        return Double.parseDouble(nextToken());
+    }
+
+    void close() throws Exception {
+        bw.flush();
+        bw.close();
+    }
+
+    void write(String content) throws Exception {
+        bw.write(content);
+    }
+
+}
+
+public class Main {
+
+    static IOController io;
+
+    //
+
+    static final int INF = (int)1e9 + 7;
+
+    static int N;
+    static int[] dep, idx;
+    static TreeSet<Integer> set;
+
+    public static void main(String[] args) throws Exception {
+
+        io = new IOController();
+
+        init();
+        solve();
+
+        io.close();
+
+    }
+
+    public static void init() throws Exception {
+
+        N = io.nextInt();
+        dep = new int[N];
+        idx = new int[N];
+        set = new TreeSet<>();
+
+    }
+
+    static void solve() throws Exception {
+
+        set.add(io.nextInt());
+        long ans = 1;
+        for(int i=1;i<N;i++) {
+            int a = io.nextInt();
+            int right = set.higher(a) == null ? -1 : set.higher(a);
+            int left = set.lower(a) == null ? -1 : set.lower(a);
+            if(right == -1) dep[a] = dep[left]+1;
+            else if(left == -1) dep[a] = dep[right]+1;
+            else {
+                if(idx[left] > idx[right]) dep[a] = dep[left]+1;
+                else dep[a] = dep[right]+1;
+            }
+            ans += dep[a]+1;
+            idx[a] = i;
+            set.add(a);
+        }
+        io.write(ans + "\n");
+
+    }
+
+}
+```