Merge pull request #2010 from AlgorithmWithGod/JHLEE325

[20260310] BOJ / G2 / 친구 네트워크 / 이준희

Author: ShinHeeEul

JHLEE325/202603/10 BOJ G2 친구 네트워크.md

@@ -0,0 +1,58 @@
+```java
+import java.io.*;
+import java.util.*;
+
+public class Main {
+    static int[] parent;
+    static int[] count;
+
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        int T = Integer.parseInt(br.readLine());
+
+        StringBuilder sb = new StringBuilder();
+        while (T-- > 0) {
+            int F = Integer.parseInt(br.readLine());
+
+            parent = new int[F * 2];
+            count = new int[F * 2];
+            for (int i = 0; i < F * 2; i++) {
+                parent[i] = i;
+                count[i] = 1;
+            }
+
+            Map<String, Integer> map = new HashMap<>();
+            int id = 0;
+
+            for (int i = 0; i < F; i++) {
+                StringTokenizer st = new StringTokenizer(br.readLine());
+                String f1 = st.nextToken();
+                String f2 = st.nextToken();
+
+                if (!map.containsKey(f1)) map.put(f1, id++);
+                if (!map.containsKey(f2)) map.put(f2, id++);
+
+                sb.append(union(map.get(f1), map.get(f2))).append("\n");
+            }
+        }
+        System.out.print(sb.toString());
+    }
+
+    static int find(int x) {
+        if (parent[x] == x) return x;
+        return parent[x] = find(parent[x]);
+    }
+
+    static int union(int x, int y) {
+        x = find(x);
+        y = find(y);
+
+        if (x != y) {
+            parent[y] = x;
+            count[x] += count[y];
+        }
+
+        return count[x];
+    }
+}
+```