diff --git "a/suyeun84/202508/21 BOJ G4 \354\232\264\353\217\231.md" "b/suyeun84/202508/21 BOJ G4 \354\232\264\353\217\231.md"
new file mode 100644
index 00000000..a77e2c3e
--- /dev/null
+++ "b/suyeun84/202508/21 BOJ G4 \354\232\264\353\217\231.md"	
@@ -0,0 +1,49 @@
+```java
+import java.util.*;
+import java.io.*;
+
+public class boj1956 {
+    static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+    static StringTokenizer st;
+    static void nextLine() throws Exception {st = new StringTokenizer(br.readLine());}
+    static int nextInt() {return Integer.parseInt(st.nextToken());}
+    static final int INF = 987654321;
+
+    public static void main(String[] args) throws Exception {
+        nextLine();
+        int V = nextInt();
+        int E = nextInt();
+        int[][] dist = new int[V+1][V+1];
+        int answer = INF;
+        for (int i = 0; i <= V; i++) {
+            Arrays.fill(dist[i], INF);
+            dist[i][i] = 0;
+        }
+        for (int i = 0; i < E; i++) {
+            nextLine();
+            int a = nextInt();
+            int b = nextInt();
+            int c = nextInt();
+            dist[a][b] = c;
+        }
+        for (int k = 1; k <= V; k++) {
+            for (int i = 1; i <= V; i++) {
+                for (int j = 1; j <= V; j++) {
+                    if (dist[i][j] > dist[i][k] + dist[k][j]) {
+                        dist[i][j] = dist[i][k] + dist[k][j];
+                    }
+                }
+            }
+        }
+        for (int i = 1; i <= V; i++) {
+            for (int j = 1; j <= V; j++) {
+                if (dist[i][j] == INF || dist[j][i] == INF) continue;
+                if (i == j) continue;
+                answer = Math.min(answer, dist[i][j] + dist[j][i]);
+            }
+        }
+        if (answer == INF) System.out.println(-1);
+        else System.out.println(answer);
+    }
+}
+```