From 911dff5f3adcba304ff79f4e733dd73fd012429f Mon Sep 17 00:00:00 2001 From: Ukj0ng <90972240+Ukj0ng@users.noreply.github.com> Date: Sun, 14 Dec 2025 11:46:35 +0900 Subject: [PATCH] =?UTF-8?q?[20251214]=20BOJ=20/=20P4=20/=20=EC=9C=A0?= =?UTF-8?q?=EB=9F=BD=EC=97=AC=ED=96=89=20/=20=ED=95=9C=EC=A2=85=EC=9A=B1?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- ...40\353\237\275\354\227\254\355\226\211.md" | 100 ++++++++++++++++++ 1 file changed, 100 insertions(+) create mode 100644 "Ukj0ng/202512/14 BOJ P4 \354\234\240\353\237\275\354\227\254\355\226\211.md" diff --git "a/Ukj0ng/202512/14 BOJ P4 \354\234\240\353\237\275\354\227\254\355\226\211.md" "b/Ukj0ng/202512/14 BOJ P4 \354\234\240\353\237\275\354\227\254\355\226\211.md" new file mode 100644 index 00000000..4f119a6d --- /dev/null +++ "b/Ukj0ng/202512/14 BOJ P4 \354\234\240\353\237\275\354\227\254\355\226\211.md" @@ -0,0 +1,100 @@ +``` +import java.io.*; +import java.util.*; + +public class Main { + private static final BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); + private static final BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out)); + private static PriorityQueue edges; + private static int[] arr, uf, size; + private static int N, P, cost; + + public static void main(String[] args) throws IOException { + init(); + int answer = MST(cost); + + bw.write(answer + "\n"); + bw.flush(); + bw.close(); + br.close(); + } + + private static void init() throws IOException { + StringTokenizer st = new StringTokenizer(br.readLine()); + N = Integer.parseInt(st.nextToken()); + P = Integer.parseInt(st.nextToken()); + cost = 1001; + + arr = new int[N+1]; + uf = new int[N+1]; + size = new int[N+1]; + + for (int i = 1; i <= N; i++) { + arr[i] = Integer.parseInt(br.readLine()); + cost = Math.min(cost, arr[i]); + uf[i] = i; + size[i] = 1; + } + + edges = new PriorityQueue<>((o1, o2) -> Integer.compare(o1.w, o2.w)); + + for (int i = 0; i < P; i++) { + st = new StringTokenizer(br.readLine()); + int s = Integer.parseInt(st.nextToken()); + int e = Integer.parseInt(st.nextToken()); + int l = Integer.parseInt(st.nextToken()); + + edges.add(new Edge(s, e, l*2 + arr[s] + arr[e])); + } + } + + private static int MST(int cost) { + int count = 0; + + while (count < N && !edges.isEmpty()) { + Edge edge = edges.poll(); + + int root1 = find(edge.u); + int root2 = find(edge.v); + + if (root1 == root2) continue; + union(edge.u, edge.v); + cost += edge.w; + count++; + } + + return cost; + } + + private static void union(int x, int y) { + int X = find(x); + int Y = find(y); + + if (size[X] < size[Y]) { + uf[X] = Y; + size[Y] += size[X]; + } else { + uf[Y] = X; + size[X] += size[Y]; + } + } + + private static int find(int x) { + if (uf[x] == x) return x; + + return uf[x] = find(uf[x]); + } + + static class Edge { + int u; + int v; + int w; + + public Edge(int u, int v, int w) { + this.u = u; + this.v = v; + this.w = w; + } + } +} +```