From 405f5b56835848f6f1c12776cada6806920ca4b0 Mon Sep 17 00:00:00 2001
From: JHLEE325 <82587652+JHLEE325@users.noreply.github.com>
Date: Fri, 1 Aug 2025 08:08:34 +0900
Subject: [PATCH] =?UTF-8?q?[20250801]=20BOJ=20/=20G4=20/=20=ED=82=A4=20?=
 =?UTF-8?q?=EC=88=9C=EC=84=9C=20/=20=EC=9D=B4=EC=A4=80=ED=9D=AC?=
MIME-Version: 1.0
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---
 ... \355\202\244 \354\210\234\354\204\234.md" | 49 +++++++++++++++++++
 1 file changed, 49 insertions(+)
 create mode 100644 "JHLEE325/202508/01 BOJ G4 \355\202\244 \354\210\234\354\204\234.md"

diff --git "a/JHLEE325/202508/01 BOJ G4 \355\202\244 \354\210\234\354\204\234.md" "b/JHLEE325/202508/01 BOJ G4 \355\202\244 \354\210\234\354\204\234.md"
new file mode 100644
index 00000000..cc20275f
--- /dev/null
+++ "b/JHLEE325/202508/01 BOJ G4 \355\202\244 \354\210\234\354\204\234.md"	
@@ -0,0 +1,49 @@
+```java
+import java.io.*;
+import java.util.*;
+
+public class Main {
+
+    public static void main(String[] args) throws Exception {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringTokenizer st = new StringTokenizer(br.readLine());
+
+        int n = Integer.parseInt(st.nextToken());
+        int m = Integer.parseInt(st.nextToken());
+        boolean[][] arr = new boolean[n][n];
+
+        for (int i = 0; i < m; i++) {
+            st = new StringTokenizer(br.readLine());
+            int a = Integer.parseInt(st.nextToken()) - 1;
+            int b = Integer.parseInt(st.nextToken()) - 1;
+            arr[a][b] = true;
+        }
+
+        for (int k = 0; k < n; k++) {
+            for (int i = 0; i < n; i++) {
+                for (int j = 0; j < n; j++) {
+                    if (arr[i][k] && arr[k][j])
+                        arr[i][j] = true;
+                }
+            }
+        }
+
+        int cnt = 0;
+        for (int i = 0; i < n; i++) {
+            boolean isknow = true;
+            for (int j = 0; j < n; j++) {
+                if (i == j)
+                    continue;
+                if (!arr[i][j] && !arr[j][i])
+                    isknow = false;
+            }
+            if (isknow)
+                cnt++;
+        }
+
+        System.out.println(cnt);
+    }
+
+}
+
+```