Create 6497번 전력난.java

Author: lamodadite

thursday/week34/haechul/6497번 전력난.java

@@ -0,0 +1,67 @@
+package BOJ.boj6497;
+
+import java.util.PriorityQueue;
+import java.util.Scanner;
+
+public class Main {
+    static int[] parents;
+    static PriorityQueue<Node> pq = new PriorityQueue<>((o1, o2) -> o1.c - o2.c);
+
+    static class Node {
+        int x;
+        int y;
+        int c;
+
+        public Node(int x, int y, int c) {
+            this.x = x;
+            this.y = y;
+            this.c = c;
+        }
+    }
+
+    public static void main(String[] args) {
+        Scanner sc = new Scanner(System.in);
+
+        while (true) {
+            int n = sc.nextInt(); // 집의 수
+            int e = sc.nextInt(); // 길의 수
+
+            if (n == 0 && e == 0) {
+                break;
+            }
+
+            parents = new int[n + 1];
+            for (int i = 1; i < n + 1; i++) {
+                parents[i] = i;
+            }
+            int total = 0;
+            for (int i = 0; i < e; i++) {
+                int x = sc.nextInt();
+                int y = sc.nextInt();
+                int c = sc.nextInt();
+                pq.add(new Node(x, y, c));
+                total += c;
+            }
+            int answer = 0;
+            while (!pq.isEmpty()) {
+                Node cur = pq.poll();
+                int px = find(cur.x);
+                int py = find(cur.y);
+                if (px == py) continue;
+                union(px, py);
+                answer += cur.c;
+            }
+
+            System.out.println(total - answer);
+        }
+    }
+    public static int find(int x) {
+        if (x == parents[x]) return x;
+        return parents[x] = find(parents[x]);
+    }
+
+    public static void union(int x, int y) {
+        if (x < y) parents[y] = parents[x];
+        else parents[x] = parents[y];
+    }
+}