結果
問題 | No.1418 Sum of Sum of Subtree Size |
ユーザー |
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提出日時 | 2023-07-12 10:03:14 |
言語 | Java (openjdk 23) |
結果 |
AC
|
実行時間 | 616 ms / 2,000 ms |
コード長 | 2,250 bytes |
コンパイル時間 | 2,816 ms |
コンパイル使用メモリ | 93,292 KB |
実行使用メモリ | 91,860 KB |
最終ジャッジ日時 | 2024-09-14 00:08:50 |
合計ジャッジ時間 | 15,710 ms |
ジャッジサーバーID (参考情報) |
judge2 / judge3 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 41 |
ソースコード
import java.io.*;import java.util.*;import java.util.stream.*;public class Main {static int n;static ArrayList<ArrayList<Integer>> graph = new ArrayList<>();static long ans = 0;public static void main(String[] args) throws Exception {Scanner sc = new Scanner();n = sc.nextInt();for (int i = 0; i < n; i++) {graph.add(new ArrayList<>());}for (int i = 0; i < n - 1; i++) {int a = sc.nextInt() - 1;int b = sc.nextInt() - 1;graph.get(a).add(b);graph.get(b).add(a);}getCount(0, 0);System.out.println(ans);}static long getCount(int idx, int p) {long count = 1;for (int x : graph.get(idx)) {if (x == p) {continue;}long tmp = getCount(x, idx);ans += tmp * (n - tmp);count += tmp;}ans += (n - count) * count + n;return count;}}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();}}