結果
問題 | No.1254 補強への架け橋 |
ユーザー |
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提出日時 | 2023-03-22 15:27:23 |
言語 | Java (openjdk 23) |
結果 |
AC
|
実行時間 | 967 ms / 2,000 ms |
コード長 | 3,953 bytes |
コンパイル時間 | 2,326 ms |
コンパイル使用メモリ | 85,324 KB |
実行使用メモリ | 102,716 KB |
最終ジャッジ日時 | 2024-09-18 14:54:52 |
合計ジャッジ時間 | 36,746 ms |
ジャッジサーバーID (参考情報) |
judge3 / judge1 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 123 |
ソースコード
import java.io.*;import java.util.*;import java.util.stream.*;public class Main {static ArrayList<HashMap<Integer, Integer>> graph = new ArrayList<>();static int[] parents;static int[] depth;public static void main(String[] args) throws Exception {Scanner sc = new Scanner();int n = sc.nextInt();for (int i = 0; i < n; i++) {graph.add(new HashMap<>());}int p = 0;int q = 0;UnionFindTree uft = new UnionFindTree(n);ArrayList<Integer> ans = new ArrayList<>();for (int i = 0; i < n; i++) {int a = sc.nextInt() - 1;int b = sc.nextInt() - 1;if (uft.same(a, b)) {p = a;q = b;ans.add(i);} else {uft.unite(a, b);graph.get(a).put(b, i);graph.get(b).put(a, i);}}parents = new int[n];depth = new int[n];setDepth(0, 0, 0);while (depth[p] != depth[q]) {if (depth[p] < depth[q]) {ans.add(graph.get(q).get(parents[q]));q = parents[q];} else {ans.add(graph.get(p).get(parents[p]));p = parents[p];}}while (p != q) {ans.add(graph.get(p).get(parents[p]));p = parents[p];ans.add(graph.get(q).get(parents[q]));q = parents[q];}StringBuilder sb = new StringBuilder();sb.append(ans.size()).append("\n");for (int i = 0; i < ans.size(); i++) {if (i > 0) {sb.append(" ");}sb.append(ans.get(i) + 1);}System.out.println(sb);}static void setDepth(int idx, int p, int d) {parents[idx] = p;depth[idx] = d;for (int x : graph.get(idx).keySet()) {if (p != x) {setDepth(x, idx, d + 1);}}}static class UnionFindTree {int[] parents;public UnionFindTree(int size) {parents = new int[size];for (int i = 0; i < size; i++) {parents[i] = i;}}public int find(int x) {if (x == parents[x]) {return x;} else {return parents[x] = find(parents[x]);}}public boolean same(int x, int y) {return find(x) == find(y);}public void unite(int x, int y) {parents[find(x)] = find(y);}}}class Utilities {static String arrayToLineString(Object[] arr) {return Arrays.stream(arr).map(x -> x.toString()).collect(Collectors.joining("\n"));}static String arrayToLineString(int[] arr) {return String.join("\n", Arrays.stream(arr).mapToObj(String::valueOf).toArray(String[]::new));}}class Scanner {BufferedReader br = new BufferedReader(new InputStreamReader(System.in));StringTokenizer st = new StringTokenizer("");StringBuilder sb = new StringBuilder();public Scanner() throws Exception {}public int nextInt() throws Exception {return Integer.parseInt(next());}public long nextLong() throws Exception {return Long.parseLong(next());}public double nextDouble() throws Exception {return Double.parseDouble(next());}public int[] nextIntArray() throws Exception {return Stream.of(br.readLine().split(" ")).mapToInt(Integer::parseInt).toArray();}public String next() throws Exception {while (!st.hasMoreTokens()) {st = new StringTokenizer(br.readLine());}return st.nextToken();}}