Merge pull request #375 from AlgorithmWithGod/Seol-JY

[20250620] BOJ / G4 / 친구비 / 설진영

Author: ShinHeeEul

Seol-JY/202506/20 BOJ G4 친구비.md

@@ -0,0 +1,78 @@
+```java
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.*;
+
+public class Main {
+    static int N, M, K;
+    static int[] prices;
+    static int[] parent;
+    static int[] minCost;
+
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        N = nextInt(st);
+        M = nextInt(st);
+        K = nextInt(st);
+
+        prices = new int[N + 1];
+        parent = new int[N + 1];
+        minCost = new int[N + 1];
+        
+        st = new StringTokenizer(br.readLine());
+        for (int i = 1; i <= N; i++) {
+            prices[i] = nextInt(st);
+            parent[i] = i;
+            minCost[i] = prices[i];
+        }
+
+        for (int i = 0; i < M; i++) {
+            st = new StringTokenizer(br.readLine());
+            union(nextInt(st), nextInt(st));
+        }
+        
+        for (int i = 1; i <= N; i++) {
+            int root = find(i);
+            minCost[root] = Math.min(minCost[root], prices[i]);
+        }
+        
+        int totalCost = 0;
+        boolean[] visited = new boolean[N + 1];
+        
+        for (int i = 1; i <= N; i++) {
+            int root = find(i);
+            if (!visited[root]) {
+                visited[root] = true;
+                totalCost += minCost[root];
+            }
+        }
+        if (totalCost <= K) {
+            System.out.println(totalCost);
+        } else {
+            System.out.println("Oh no");
+        }
+    }
+    
+    private static int find(int x) {
+        if (parent[x] != x) {
+            parent[x] = find(parent[x]);
+        }
+        
+        return parent[x];
+    }
+    
+    private static void union(int x, int y) {
+        int rootX = find(x);
+        int rootY = find(y);
+        if (rootX != rootY) {
+            parent[rootY] = rootX;
+        }
+    }
+
+    private static int nextInt(StringTokenizer st) {
+        return Integer.parseInt(st.nextToken());
+    }
+}
+```