diff --git "a/khj20006/202509/18 BOJ G4 \353\223\244\355\214\220 \352\261\264\353\204\210\352\260\200\352\270\260.md" "b/khj20006/202509/18 BOJ G4 \353\223\244\355\214\220 \352\261\264\353\204\210\352\260\200\352\270\260.md"
new file mode 100644
index 00000000..50632f92
--- /dev/null
+++ "b/khj20006/202509/18 BOJ G4 \353\223\244\355\214\220 \352\261\264\353\204\210\352\260\200\352\270\260.md"	
@@ -0,0 +1,86 @@
+```java
+import java.io.*;
+import java.util.*;
+
+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 int N;
+	static int[] dp;
+
+	public static void main(String[] args) throws Exception {
+
+		io = new IOController();
+
+		N = io.nextInt()-1;
+		
+		dp = new int[101];
+		Arrays.fill(dp, -1);
+		dp[io.nextInt()] = 0;
+		
+		while(N-->0) {
+		    int a = io.nextInt();
+		    int max = 0;
+		    for(int j=1;j<=100;j++) if(dp[j] != -1) max = Math.max(max, dp[j] + (j-a)*(j-a));
+		    dp[a] = Math.max(dp[a], max);
+		}
+		
+		int ans = 0;
+		for(int i=1;i<=100;i++) ans = Math.max(ans, dp[i]);
+		io.write(ans + "\n");
+
+		io.close();
+
+	}
+
+}
+```