結果
| 問題 | No.1507 Road Blocked |
| ユーザー |
 遭難者
|
| 提出日時 | 2021-04-06 14:49:23 |
| 言語 | Java (openjdk 23) |
| 結果 |
AC
|
| 実行時間 | 353 ms / 2,000 ms |
| コード長 | 15,763 bytes |
| コンパイル時間 | 3,212 ms |
| コンパイル使用メモリ | 90,500 KB |
| 実行使用メモリ | 95,072 KB |
| 最終ジャッジ日時 | 2024-06-11 21:22:22 |
| 合計ジャッジ時間 | 14,903 ms |
|
ジャッジサーバーID （参考情報） |
judge5 / judge3 |
（要ログイン）
| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 30 |
ソースコード
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]);
}
}
}