結果
| 問題 | No.3476 {2^n-1}-gon |
| コンテスト | |
| ユーザー |
 37zigen
|
| 提出日時 | 2026-03-21 00:51:05 |
| 言語 | Java (openjdk 25.0.2) |
| 結果 |
AC
|
| 実行時間 | 299 ms / 2,000 ms |
| コード長 | 9,804 bytes |
| 記録 | |
| コンパイル時間 | 2,808 ms |
| コンパイル使用メモリ | 103,592 KB |
| 実行使用メモリ | 47,208 KB |
| 最終ジャッジ日時 | 2026-03-21 00:51:14 |
| 合計ジャッジ時間 | 5,990 ms |
|
ジャッジサーバーID （参考情報） |
judge3_0 / judge2_0 |
（要ログイン）
| ファイルパターン | 結果 |
|---|---|
| sample | AC * 2 |
| other | AC * 18 |
ソースコード
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.lang.reflect.Array;
import java.math.BigInteger;
import java.nio.file.Files;
import java.nio.file.OpenOption;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.Deque;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map.Entry;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Optional;
import java.util.Queue;
import java.util.Random;
import java.util.Set;
import java.util.TreeMap;
import java.util.TreeSet;
import java.util.function.BiFunction;
import java.util.function.Consumer;
import java.util.function.DoubleUnaryOperator;
import java.util.function.Function;
import java.util.function.IntBinaryOperator;
import java.util.function.IntFunction;
import java.util.function.IntToDoubleFunction;
import java.util.function.IntToLongFunction;
import java.util.function.IntUnaryOperator;
import java.util.function.LongBinaryOperator;
import java.util.function.LongToDoubleFunction;
import java.util.function.Predicate;
import java.util.function.Supplier;
import java.util.function.ToIntFunction;
import java.util.random.RandomGenerator;
import java.util.stream.IntStream;
import java.util.stream.Stream;
class FastScanner {
private static FastScanner instance = null;
private final InputStream in = System.in;
private final byte[] buffer = new byte[1024];
private int ptr = 0;
private int buflen = 0;
private FastScanner() {
}
public static FastScanner getInstance() {
if (instance == null) {
instance = new FastScanner();
}
return instance;
}
private boolean hasNextByte() {
if (ptr < buflen) {
return true;
}
ptr = 0;
try {
buflen = in.read(buffer);
} catch (IOException e) {
e.printStackTrace();
}
return buflen > 0;
}
private int readByte() {
if (hasNextByte()) {
return buffer[ptr++];
} else {
return -1;
}
}
private boolean isPrintableChar(int c) {
return (33 <= c) && (c <= 126);
}
public boolean hasNext() {
while (hasNextByte() && (!isPrintableChar(buffer[ptr]))) {
ptr++;
}
return hasNextByte();
}
public long nextLong() {
if (!hasNext()) {
throw new NoSuchElementException();
}
long n = 0;
boolean minus = false;
int b = readByte();
if (b == '-') {
minus = true;
b = readByte();
}
while ((b >= '0') && (b <= '9')) {
// n = n * 10 + (b - '0');
n = ((n << 1) + (n << 3)) + (b - '0');
b = readByte();
}
return minus ? -n : n;
}
public int nextInt() {
return ((int) (nextLong()));
}
}
class MergeFiles {}
class Zn {
final long mod;
public Zn(long mod) {
this.mod = mod;
}
/**
* *
* 剰余を取り、0以上mod未満の値を返す。
*
* @param a
* @return */
public long reduce(long a) {
a %= mod;
if (a < 0) {
a += mod;
}
return a;
}
}
class ArrayUtils {
public static void swap(long[] A, long[] B) {
if (A.length != B.length) {
throw new AssertionError();
}
for (int i = 0; i < A.length; i++) {
long tmp = A[i];
A[i] = B[i];
B[i] = tmp;
}
}
}
class MyPrintWriter extends PrintWriter {
private static MyPrintWriter instance = null;
private MyPrintWriter() {
super(System.out);
}
public static MyPrintWriter getInstance() {
if (instance == null) {
instance = new MyPrintWriter();
}
return instance;
}
public void println(boolean[][] a) {
for (int i = 0; i < a.length; i++) {
println(a[i], " ");
}
}
public void println(boolean[] a, String separator) {
for (int i = 0; i < a.length; ++i) {
super.print((a[i] ? 1 : 0) + (i == (a.length - 1) ? "\n" : separator));
}
}
}
class Fp extends Zn {
public Fp(long mod) {
super(mod);
}
long[] inv = new long[0];
public long inv(long n) {
if (n < 0) {
n = reduce(n);
}
return n < inv.length ? inv[((int) (n))] : MathUtils.modInv(n, mod);
}
public long combNaive(long n, long k) {
if ((k < 0) || ((n - k) < 0)) {
return 0;
}
k = Math.min(k, n - k);
long ret = 1;
for (int i = 0; i < k; i++) {
ret = (ret * (n - i)) % mod;
ret = (ret * inv(i + 1)) % mod;
}
return ret;
}
public long pow(long a, long n) {
return MathUtils.modPow(a, n, mod);
}
}
class MathUtils {
public static long modPow(long a, long n, long mod) {
if (n < 0) {
long inv = MathUtils.modInv(a, mod);
return MathUtils.modPow(inv, -n, mod);
}
if (n == 0) {
return 1;
}
return (MathUtils.modPow((a * a) % mod, n / 2, mod) * ((n % 2) == 1 ? a : 1)) % mod;
}
/**
* 拡張ユークリッドの互除法で逆元を求める。
*
* @param a
* @param mod
* @return */
public static long modInv(long a, long mod) {
a = ((a % mod) + mod) % mod;
long[] f0 = new long[]{ 1, 0, mod };
long[] f1 = new long[]{ 0, 1, a };
while (f1[2] != 0) {
long q = f0[2] / f1[2];
for (int i = 0; i < 3; i++) {
f0[i] -= q * f1[i];
}
ArrayUtils.swap(f0, f1);
}
return f0[1] < 0 ? mod + f0[1] : f0[1];
}
}
public class Main implements Runnable {
public static void main(String[] args) throws IOException {
Thread.setDefaultUncaughtExceptionHandler((t, e) -> System.exit(1));
// Runtime runtime = Runtime.getRuntime();
// new Thread(null, new Main(), "MainThreadWithLargeStack", (1024 * 1024) * 1024).start();
// new Main().test();
// new Main().gen();
new Main().run();
// long usedMemory = runtime.totalMemory() - runtime.freeMemory();
// System.err.printf("使用メモリ: %.2f MB%n", usedMemory / 1024.0 / 1024.0);
MyPrintWriter.getInstance().flush();
}
@Override
public void run() {
FastScanner sc = FastScanner.getInstance();
MyPrintWriter pw = MyPrintWriter.getInstance();
long mod = 998244353;
int N = sc.nextInt();
int M = sc.nextInt();
Fp fp = new Fp(mod);
long q = fp.pow(2, N) - 1;
q = fp.reduce(q);
long ans = fp.combNaive(q, M);
long n = fp.pow(2, N - 1);// (2^n)-1で2^(n-1)-1がすでに占有済み。残り2^(n-1)
long x = (fp.combNaive(n, M) * fp.inv(n)) % mod;
x = (x * q) % mod;
ans -= x * M;
ans = fp.reduce(ans);
pw.println(ans);
}
}
// --- Original Code ---
// package template;
//
// import java.io.IOException;
// import java.nio.file.Files;
// import java.nio.file.Path;
// import java.util.Arrays;
// import java.util.List;
// import java.util.Random;
//
// import library.tools.FastScanner;
// import library.tools.MergeFiles;
// import library.tools.MyPrintWriter;
// import library.util.Fp;
// import library.util.MathUtils;
// import library.util.polynomial.PolynomialFp;
//
// public class Main implements Runnable {
//
// public static void main(String[] args) throws IOException {
// // Runtime runtime = Runtime.getRuntime();
// // new Thread(null, new Main(), "MainThreadWithLargeStack", (1024 * 1024) * 1024).start();
// // new Main().test();
// // new Main().gen();
// new Main().run();
// // long usedMemory = runtime.totalMemory() - runtime.freeMemory();
// // System.err.printf("使用メモリ: %.2f MB%n", usedMemory / 1024.0 / 1024.0);
// MyPrintWriter.getInstance().flush();
// MergeFiles.export();
// }
//
// @Override
// public void run() {
// FastScanner sc = FastScanner.getInstance();
// MyPrintWriter pw = MyPrintWriter.getInstance();
//
// long mod = 998244353;
// int N = sc.nextInt();
// int M = sc.nextInt();
// Fp fp = new Fp(mod);
// long q = fp.pow(2, N) - 1;
// q = fp.reduce(q);
// long ans = fp.combNaive(q, M);
// long n = fp.pow(2, N - 1);// (2^n)-1で2^(n-1)-1がすでに占有済み。残り2^(n-1)
// long x = fp.combNaive(n, M) * fp.inv(n) % mod;
// x = (x * q) % mod;
// ans -= x * M;
// ans = fp.reduce(ans);
// pw.println(ans);
// }
//
// void abc() {
// Random rnd = new Random();
// try {
// List<String> candidates = Files.readAllLines(Path.of("problems.txt")).stream()
// .filter(line -> !line.contains("o")).map(line -> line.split("\\s+")[0]).toList();
//
// String problem = candidates.get(rnd.nextInt(candidates.size()));
// System.out.println(problem);
//
// } catch (IOException e) {
// e.printStackTrace();
// }
// }
//
// void tr(Object... objects) {
// System.out.println(Arrays.deepToString(objects));
// }
// }
//