[20250725] BOJ / P4 / Four XOR / 권혁준

Author: oncsr

khj20006/202507/25 BOJ P4 Four XOR.md

@@ -0,0 +1,98 @@
+```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 int N;
+    static int[] a;
+
+    public static void main(String[] args) throws Exception {
+
+        io = new IOController();
+
+        init();
+        solve();
+
+        io.close();
+
+    }
+
+    static void init() throws Exception {
+
+        N = io.nextInt();
+        a = new int[N];
+        for(int i=0;i<N;i++) a[i] = io.nextInt();
+
+    }
+
+    static void solve() throws Exception {
+
+        if(N >= 5000) {
+            io.write("Yes");
+            return;
+        }
+
+        boolean[] cnt = new boolean[131072];
+        for(int i=0;i<N;i++) for(int j=i+1;j<N;j++) {
+            if(cnt[a[i]^a[j]]) {
+                io.write("Yes");
+                return;
+            }
+            cnt[a[i]^a[j]] = true;
+        }
+        io.write("No");
+
+    }
+
+}
+```