From 0572cdf2d448fd7467ffe07db813666b98511c59 Mon Sep 17 00:00:00 2001 From: JHLEE325 <82587652+JHLEE325@users.noreply.github.com> Date: Fri, 13 Mar 2026 15:29:37 +0900 Subject: [PATCH] =?UTF-8?q?[20260313]=20BOJ=20/=20G4=20/=20=ED=96=89?= =?UTF-8?q?=EC=84=B1=20=EC=97=B0=EA=B2=B0=20/=20=EC=9D=B4=EC=A4=80?= =?UTF-8?q?=ED=9D=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- ...1\354\204\261 \354\227\260\352\262\260.md" | 74 +++++++++++++++++++ 1 file changed, 74 insertions(+) create mode 100644 "JHLEE325/202603/13 BOJ G4 \355\226\211\354\204\261 \354\227\260\352\262\260.md" diff --git "a/JHLEE325/202603/13 BOJ G4 \355\226\211\354\204\261 \354\227\260\352\262\260.md" "b/JHLEE325/202603/13 BOJ G4 \355\226\211\354\204\261 \354\227\260\352\262\260.md" new file mode 100644 index 00000000..8f78d6b3 --- /dev/null +++ "b/JHLEE325/202603/13 BOJ G4 \355\226\211\354\204\261 \354\227\260\352\262\260.md" @@ -0,0 +1,74 @@ +```java +import java.io.*; +import java.util.*; + +class Edge implements Comparable { + int u, v, weight; + + public Edge(int u, int v, int weight) { + this.u = u; + this.v = v; + this.weight = weight; + } + + @Override + public int compareTo(Edge o) { + return this.weight - o.weight; + } +} + +public class Main { + + static int[] parent; + + public static void main(String[] args) throws IOException { + BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); + int N = Integer.parseInt(br.readLine()); + + List edges = new ArrayList<>(); + for (int i = 0; i < N; i++) { + StringTokenizer st = new StringTokenizer(br.readLine()); + for (int j = 0; j < N; j++) { + int weight = Integer.parseInt(st.nextToken()); + if (i < j) { + edges.add(new Edge(i, j, weight)); + } + } + } + + Collections.sort(edges); + + parent = new int[N]; + for (int i = 0; i < N; i++) parent[i] = i; + + long cost = 0; + int count = 0; + + for (Edge edge : edges) { + if (union(edge.u, edge.v)) { + cost += edge.weight; + count++; + if (count == N - 1) break; + } + } + + System.out.println(cost); + } + + static int find(int x) { + if (parent[x] == x) return x; + return parent[x] = find(parent[x]); + } + + static boolean union(int x, int y) { + x = find(x); + y = find(y); + + if (x != y) { + parent[y] = x; + return true; + } + return false; + } +} +```