結果

問題 No.1507 Road Blocked
ユーザー 遭難者遭難者
提出日時 2021-04-06 14:49:23
言語 Java17
(openjdk 17.0.1)
結果
AC  
実行時間 329 ms / 2,000 ms
コード長 15,763 bytes
コンパイル時間 2,598 ms
使用メモリ 82,800 KB
最終ジャッジ日時 2023-01-18 21:21:10
合計ジャッジ時間 15,752 ms
ジャッジサーバーID
(参考情報)
judge14 / judge15
このコードへのチャレンジ(β)

テストケース

テストケース表示
入力 結果 実行時間
使用メモリ
testcase_00 AC 51 ms
33,960 KB
testcase_01 AC 51 ms
33,900 KB
testcase_02 AC 50 ms
33,908 KB
testcase_03 AC 267 ms
82,800 KB
testcase_04 AC 307 ms
55,508 KB
testcase_05 AC 314 ms
60,364 KB
testcase_06 AC 314 ms
60,304 KB
testcase_07 AC 306 ms
54,940 KB
testcase_08 AC 322 ms
60,524 KB
testcase_09 AC 306 ms
60,360 KB
testcase_10 AC 329 ms
60,408 KB
testcase_11 AC 290 ms
60,272 KB
testcase_12 AC 316 ms
60,400 KB
testcase_13 AC 311 ms
60,548 KB
testcase_14 AC 298 ms
55,372 KB
testcase_15 AC 325 ms
60,280 KB
testcase_16 AC 294 ms
54,800 KB
testcase_17 AC 288 ms
60,128 KB
testcase_18 AC 309 ms
60,196 KB
testcase_19 AC 313 ms
60,508 KB
testcase_20 AC 300 ms
55,236 KB
testcase_21 AC 323 ms
60,364 KB
testcase_22 AC 302 ms
60,112 KB
testcase_23 AC 316 ms
60,380 KB
testcase_24 AC 294 ms
54,392 KB
testcase_25 AC 320 ms
60,412 KB
testcase_26 AC 294 ms
55,384 KB
testcase_27 AC 305 ms
60,132 KB
testcase_28 AC 283 ms
55,548 KB
testcase_29 AC 289 ms
60,124 KB
testcase_30 AC 326 ms
60,428 KB
testcase_31 AC 296 ms
60,216 KB
testcase_32 AC 317 ms
60,500 KB
権限があれば一括ダウンロードができます

ソースコード

diff #

import java.util.*;
import java.io.*;

public class Main {
    public static void solve(ContestScanner sc, ContestPrinter ou) {
        int n = sc.nextInt();
        d = new int[n];
        var k = new int[n - 1][2];
        for (int i = 0; i < n; i++)
            g.add(new ArrayList<>());
        for (int i = 0; i < n - 1; i++) {
            int l = sc.nextInt() - 1;
            int r = sc.nextInt() - 1;
            g.get(l).add(r);
            g.get(r).add(l);
            k[i][0] = l;
            k[i][1] = r;
        }
        search(0, -1);
        long s = 0;
        for (int i = 0; i < n - 1; i++) {
            long m = min(d[k[i][0]], d[k[i][1]]) + 1;
            m *= n - m;
            m %= mod;
            s += m;
            s %= mod;
        }
        long b = n - 1;
        b *= n - 1;
        b %= mod;
        b *= n;
        b %= mod;
        if (b % 2 == 1)
            b += mod;
        b /= 2;
        s = b - s;
        s %= mod;
        if (s < 0)
            s += mod;
        s *= mp(b, mod - 2, mod);
        s %= mod;
        ou.println(s);
    }

    public static ArrayList<ArrayList<Integer>> g = new ArrayList<ArrayList<Integer>>();
    public static int[] d;
    public static int mod = 998244353;

    public static int search(int a, int b) {
        for (int i : g.get(a)) {
            if (i != b)
                d[a] += search(i, a);
        }
        return d[a] + 1;
    }

    static long mp(long a, long b, long m) {
        if (b == 0)
            return 1;
        if ((b & 1) == 1)
            return (a * mp(a, b - 1, m)) % m;
        return mp((a * a) % m, b >> 1, m);
    }

    public static void main(String[] args) {
        var sc = new ContestScanner();
        var ou = new ContestPrinter();
        solve(sc, ou);
        ou.flush();
        ou.close();
    }

    public static int max(int s, int... a) {
        for (int i : a)
            if (s < i)
                s = i;
        return s;
    }

    public static long max(long s, long... a) {
        for (long i : a)
            if (s < i)
                s = i;
        return s;
    }

    public static int min(int s, int... a) {
        for (int i : a)
            if (s > i)
                s = i;
        return s;
    }

    public static long min(long s, long... a) {
        for (long i : a)
            if (s > i)
                s = i;
        return s;
    }

    static class Point {
        int x;
        int y;

        Point(int x, int y) {
            this.x = x;
            this.y = y;
        }

        int compareTo(Point p) {
            long c = this.x - p.x;
            if (c < 0)
                return -1;
            if (c > 0)
                return 1;
            return 0;
        }

        boolean equals(Point p) {
            return this.x == p.x && this.y == p.y;
        }
    }

    static class Point2 {
        long x;
        int y;

        Point2(long x, int y) {
            this.x = x;
            this.y = y;
        }

        int compareTo(Point2 p) {
            long c = this.x - p.x;
            if (c < 0)
                return -1;
            if (c > 0)
                return 1;
            return 0;
        }

        boolean equals(Point2 p) {
            return this.x == p.x && this.y == p.y;
        }
    }
}

class ContestScanner {
    private final InputStream in;
    private final byte[] buffer = new byte[1024];
    private int ptr = 0;
    private int buflen = 0;

    public ContestScanner(InputStream in) {
        this.in = in;
    }

    public ContestScanner() {
        this(System.in);
    }

    private boolean hasNextByte() {
        if (ptr < buflen)
            return true;
        ptr = 0;
        try {
            buflen = in.read(buffer);
        } catch (IOException e) {
            e.printStackTrace();
        }
        if (buflen <= 0)
            return false;
        return true;
    }

    private int readByte() {
        return hasNextByte() ? buffer[ptr++] : -1;
    }

    private static boolean isPrintableChar(int c) {
        return 33 <= c && c <= 126;
    }

    public boolean hasNext() {
        while (hasNextByte() && !isPrintableChar(buffer[ptr]))
            ptr++;
        return hasNextByte();
    }

    public String next() {
        if (!hasNext())
            throw new NoSuchElementException();
        StringBuilder sb = new StringBuilder();
        int b = readByte();
        while (isPrintableChar(b)) {
            sb.appendCodePoint(b);
            b = readByte();
        }
        return sb.toString();
    }

    public void nextThrow(int n) {
        for (int i = 0; i < n; i++)
            this.next();
    }

    public void nextThrow() {
        this.nextThrow(1);
    }

    public long nextLong() {
        if (!hasNext())
            throw new NoSuchElementException();
        long n = 0;
        boolean minus = false;
        int b = readByte();
        if (b == '-') {
            minus = true;
            b = readByte();
        }
        if (b < '0' || '9' < b)
            throw new NumberFormatException();
        while (true) {
            if ('0' <= b && b <= '9') {
                n *= 10;
                n += b - '0';
            } else if (b == -1 || !isPrintableChar(b))
                return minus ? -n : n;
            else
                throw new NumberFormatException();
            b = readByte();
        }
    }

    public int nextInt() {
        long nl = nextLong();
        if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE)
            throw new NumberFormatException();
        return (int) nl;
    }

    public double nextDouble() {
        return Double.parseDouble(next());
    }

    public boolean[] nextBoolean(char True) {
        String s = this.next();
        int n = s.length();
        boolean[] array = new boolean[n];
        for (int i = 0; i < n; i++)
            array[i] = s.charAt(i) == True;
        return array;
    }

    public long[] nextLongArray(int length) {
        long[] array = new long[length];
        for (int i = 0; i < length; i++)
            array[i] = this.nextLong();
        return array;
    }

    public long[] nextLongArray(int length, java.util.function.LongUnaryOperator map) {
        long[] array = new long[length];
        for (int i = 0; i < length; i++)
            array[i] = map.applyAsLong(this.nextLong());
        return array;
    }

    public int[] nextIntArray(int length) {
        int[] array = new int[length];
        for (int i = 0; i < length; i++)
            array[i] = this.nextInt();
        return array;
    }

    public int[] nextIntArray(int length, java.util.function.IntUnaryOperator map) {
        int[] array = new int[length];
        for (int i = 0; i < length; i++)
            array[i] = map.applyAsInt(this.nextInt());
        return array;
    }

    public int[] nextIntArray(int length, int[] array) {
        int n = length + array.length;
        int[] a = new int[n];
        for (int i = 0; i < length; i++)
            a[i] = this.nextInt();
        for (int i = length; i < n; i++)
            a[i] = array[i - length];
        return a;
    }

    public Integer[] nextIntegerArray(int length, java.util.function.IntUnaryOperator map) {
        Integer[] array = new Integer[length];
        for (int i = 0; i < length; i++)
            array[i] = map.applyAsInt(this.nextInt());
        return array;
    }

    public Integer[] nextIntegerArray(int length) {
        Integer[] array = new Integer[length];
        for (int i = 0; i < length; i++)
            array[i] = this.nextInt();
        return array;
    }

    public double[] nextDoubleArray(int length) {
        double[] array = new double[length];
        for (int i = 0; i < length; i++)
            array[i] = this.nextDouble();
        return array;
    }

    public double[] nextDoubleArray(int length, java.util.function.DoubleUnaryOperator map) {
        double[] array = new double[length];
        for (int i = 0; i < length; i++)
            array[i] = map.applyAsDouble(this.nextDouble());
        return array;
    }

    public String[] nextArray(int length) {
        String[] array = new String[length];
        for (int i = 0; i < length; i++)
            array[i] = this.next();
        return array;
    }

    public long[][] nextLongMatrix(int height, int width) {
        long[][] mat = new long[height][width];
        for (int h = 0; h < height; h++)
            for (int w = 0; w < width; w++)
                mat[h][w] = this.nextLong();
        return mat;
    }

    public int[][] nextIntMatrix(int height, int width) {
        int[][] mat = new int[height][width];
        for (int h = 0; h < height; h++)
            for (int w = 0; w < width; w++)
                mat[h][w] = this.nextInt();
        return mat;
    }

    public double[][] nextDoubleMatrix(int height, int width) {
        double[][] mat = new double[height][width];
        for (int h = 0; h < height; h++)
            for (int w = 0; w < width; w++)
                mat[h][w] = this.nextDouble();
        return mat;
    }

    public boolean[][] nextBooleanMatrix(int height, int width, char True) {
        boolean[][] mat = new boolean[height][width];
        for (int h = 0; h < height; h++) {
            String s = this.next();
            for (int w = 0; w < width; w++)
                mat[h][w] = s.charAt(w) == True;
        }
        return mat;
    }

    public char[][] nextCharMatrix(int height, int width) {
        char[][] mat = new char[height][width];
        for (int h = 0; h < height; h++) {
            String s = this.next();
            for (int w = 0; w < width; w++)
                mat[h][w] = s.charAt(w);
        }
        return mat;
    }

    public char[][] nextCharMatrix(int height, int width, int h, int w, char c) {
        char[][] mat = new char[height + 2 * h][width + 2 * w];
        for (int i = 0; i < height; i++) {
            String s = this.next();
            for (int j = 0; j < width; j++)
                mat[i + h][j + w] = s.charAt(j);
        }
        for (int i = 0; i < h; i++)
            for (int j = 0; j < 2 * w + width; j++)
                mat[i][j] = c;
        for (int i = h + height; i < 2 * h + height; i++)
            for (int j = 0; j < 2 * w + width; j++)
                mat[i][j] = c;
        for (int i = h; i < h + height; i++) {
            for (int j = 0; j < w; j++)
                mat[i][j] = c;
            for (int j = w + width; j < 2 * w + width; j++)
                mat[i][j] = c;
        }
        return mat;
    }

    public boolean[][] nextBooleanMatrix(int height, int width, int h, int w, char c) {
        boolean[][] mat = new boolean[height + 2 * h][width + 2 * w];
        for (int i = 0; i < height; i++) {
            String s = this.next();
            for (int j = 0; j < width; j++)
                mat[i + h][j + w] = s.charAt(j) == c;
        }
        return mat;
    }
}

class ContestPrinter extends PrintWriter {
    public ContestPrinter(PrintStream stream) {
        super(stream);
    }

    public ContestPrinter() {
        super(System.out);
    }

    private static String dtos(double x, int n) {
        StringBuilder sb = new StringBuilder();
        if (x < 0) {
            sb.append('-');
            x = -x;
        }
        x += Math.pow(10, -n) / 2;
        sb.append((long) x);
        sb.append(".");
        x -= (long) x;
        for (int i = 0; i < n; i++) {
            x *= 10;
            sb.append((int) x);
            x -= (int) x;
        }
        return sb.toString();
    }

    @Override
    public void print(float f) {
        super.print(dtos(f, 20));
    }

    @Override
    public void println(float f) {
        super.println(dtos(f, 20));
    }

    @Override
    public void print(double d) {
        super.print(dtos(d, 20));
    }

    @Override
    public void println(double d) {
        super.println(dtos(d, 20));
    }

    public void printlnArray(String[] array) {
        for (String i : array)
            super.println(i);
    }

    public void printArray(int[] array, String separator) {
        int n = array.length - 1;
        for (int i = 0; i < n; i++) {
            super.print(array[i]);
            super.print(separator);
        }
        super.println(array[n]);
    }

    public void printArray(int[] array) {
        this.printArray(array, " ");
    }

    public void printlnArray(int[] array) {
        for (int i : array)
            super.println(i);
    }

    public void printArray(int[] array, String separator, java.util.function.IntUnaryOperator map) {
        int n = array.length - 1;
        for (int i = 0; i < n; i++) {
            super.print(map.applyAsInt(array[i]));
            super.print(separator);
        }
        super.println(map.applyAsInt(array[n]));
    }

    public void printlnArray(int[] array, java.util.function.IntUnaryOperator map) {
        for (int i : array)
            super.println(map.applyAsInt(i));
    }

    public void printlnArray(long[] array, java.util.function.LongUnaryOperator map) {
        for (long i : array)
            super.println(map.applyAsLong(i));
    }

    public void printArray(int[] array, java.util.function.IntUnaryOperator map) {
        this.printArray(array, " ", map);
    }

    public void printArray(long[] array, String separator) {
        int n = array.length - 1;
        for (int i = 0; i < n; i++) {
            super.print(array[i]);
            super.print(separator);
        }
        super.println(array[n]);
    }

    public void printArray(long[] array) {
        this.printArray(array, " ");
    }

    public void printlnArray(long[] array) {
        for (long i : array)
            super.println(i);
    }

    public void printArray(boolean[] array, String a, String b) {
        int n = array.length - 1;
        for (int i = 0; i < n; i++)
            super.print((array[i] ? a : b) + " ");
        super.println(array[n] ? a : b);
    }

    public void printArray(boolean[] array) {
        this.printArray(array, "Y", "N");
    }

    public void printArray(long[] array, String separator, java.util.function.LongUnaryOperator map) {
        int n = array.length - 1;
        for (int i = 0; i < n; i++) {
            super.print(map.applyAsLong(array[i]));
            super.print(separator);
        }
        super.println(map.applyAsLong(array[n]));
    }

    public void printArray(long[] array, java.util.function.LongUnaryOperator map) {
        this.printArray(array, " ", map);
    }

    public void printArray(ArrayList<?> array) {
        this.printArray(array, " ");
    }

    public void printArray(ArrayList<?> array, String separator) {
        int n = array.size() - 1;
        for (int i = 0; i < n; i++) {
            super.print(array.get(i).toString());
            super.print(separator);
        }
        super.println(array.get(n).toString());
    }

    public void printlnArray(ArrayList<?> array) {
        int n = array.size();
        for (int i = 0; i < n; i++)
            super.println(array.get(i).toString());
    }

    public void printArray(int[][] array) {
        int n = array.length;
        if (n == 0)
            return;
        int m = array[0].length - 1;
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < m; j++)
                super.print(array[i][j] + " ");
            super.println(array[i][m]);
        }
    }

    public void printArray(long[][] array) {
        int n = array.length;
        if (n == 0)
            return;
        int m = array[0].length - 1;
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < m; j++)
                super.print(array[i][j] + " ");
            super.println(array[i][m]);
        }
    }
}
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