Merge pull request #652 from AlgorithmWithGod/suyeun84

[20250812] BOJ / G5 / 세 친구 / 김수연

Author: ShinHeeEul

suyeun84/202508/12 BOJ G5 세 친구.md

@@ -0,0 +1,45 @@
+```java
+import java.io.*;
+import java.util.*;
+
+public class boj17089 {
+	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());}
+
+	public static void main(String[] args) throws Exception {
+		nextLine();
+		int N = nextInt();
+		int M = nextInt();
+		boolean[][] friend = new boolean[N+1][N+1];
+        int[] count = new int[N+1];
+		for (int i = 0; i < M; i++) {
+			nextLine();
+			int a = nextInt();
+			int b = nextInt();
+			friend[a][b] = true;
+			friend[b][a] = true;
+			count[a]++;
+			count[b]++;
+		}
+		
+		int min = Integer.MAX_VALUE;
+
+        for(int A = 1; A < N+1; A++) {
+            for(int B = A+1; B < N+1; B++) {
+                if(!friend[A][B]) continue;
+                for(int C = B+1; C < N+1; C++) {
+                    if(!friend[C][A] || !friend[C][B]) continue;
+
+                    int sum = count[A] + count[B] + count[C] - 6;
+                    min = Math.min(min, sum);
+                }
+            }
+        }
+
+        if(min == Integer.MAX_VALUE) System.out.println(-1);
+        else System.out.println(min);
+	}
+}
+```