結果
問題 | No.2327 Inversion Sum |
ユーザー |
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提出日時 | 2023-05-28 14:46:43 |
言語 | Java (openjdk 23) |
結果 |
AC
|
実行時間 | 363 ms / 2,000 ms |
コード長 | 11,323 bytes |
コンパイル時間 | 5,020 ms |
コンパイル使用メモリ | 93,528 KB |
実行使用メモリ | 46,180 KB |
最終ジャッジ日時 | 2024-12-27 02:56:13 |
合計ジャッジ時間 | 12,156 ms |
ジャッジサーバーID (参考情報) |
judge5 / judge4 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 30 |
ソースコード
public class Main {public static void main(String[] args) {new Main();}public Main() {FastScanner fs = new FastScanner();java.io.PrintWriter out = new java.io.PrintWriter(System.out);solve(fs, out);out.flush();}public void solve(FastScanner fs, java.io.PrintWriter out) {int N = fs.nextInt(), M = fs.nextInt();int[][] val = new int[M][2];for (int i = 0;i < M;++ i) {val[i][0] = fs.nextInt() - 1;val[i][1] = fs.nextInt() - 1;}java.util.Arrays.sort(val, (l, r) -> Integer.compare(l[1], r[1]));int[] cp = new int[M];for (int i = 0;i < M;++ i) cp[i] = val[i][0];int[] array = new int[N];java.util.Arrays.fill(array, -1);for (int[] i : val) array[i[1]] = i[0];int ans = 0;calc(N);if (N - M >= 2) {int tmp = comb(N - M, 2);tmp = times(tmp, tmp);tmp = times(tmp, fact[N - M - 2]);ans = plus(ans, tmp);}for (int x = 0;x < 2 && N - M >= 1;++ x) {FenwickTree sum = new FenwickTree(N);for (int i = 0;i < N;++ i) sum.set(i, 1);for (int i : cp) sum.set(i, 0);int any = 0;int tmp = 0;for (int i : array) {if (i == -1) {++ any;continue;}int tmp2 = x == 0 ? (int)sum.sum(i, N) : (int)sum.sum(0, i);tmp2 = times(tmp2, any);tmp = plus(tmp, tmp2);}tmp = times(tmp, fact[N - M - 1]);ans = plus(ans, tmp);for (int l = 0, r = N - 1;l < r;++ l, -- r) {array[l] ^= array[r];array[r] ^= array[l];array[l] ^= array[r];}}FenwickTree sum = new FenwickTree(N);int tmp = 0;for (int i : cp) {tmp = plus(tmp, (int)sum.sum(i, N));sum.add(i, 1);}tmp = times(tmp, fact[N - M]);ans = plus(ans, tmp);out.println(ans);}class FenwickTree{private int _n;private long[] data;public FenwickTree(int n){_n = n;data = new long[n];}/*** @verified https://atcoder.jp/contests/practice2/tasks/practice2_b* @submission https://atcoder.jp/contests/practice2/submissions/16580495*/public FenwickTree(long[] data) {this(data.length);build(data);}public void set(int p, long x){add(p, x - get(p));}public void add(int p, long x){assert 0<=p && p<_n;p++;while(p<=_n){data[p-1] += x;p += p&-p;}}public long sum(int l, int r){assert 0<=l && l<=r && r<=_n;return sum(r)-sum(l);}public long get(int p){return sum(p, p+1);}private long sum(int r){long s = 0;while(r>0){s += data[r-1];r -= r&-r;}return s;}private void build(long[] dat) {System.arraycopy(dat, 0, data, 0, _n);for (int i=1; i<=_n; i++) {int p = i+(i&-i);if(p<=_n){data[p-1] += data[i-1];}}}}final int MOD = 998_244_353;int plus(int n, int m) {int sum = n + m;if (sum >= MOD) sum -= MOD;return sum;}int minus(int n, int m) {int sum = n - m;if (sum < 0) sum += MOD;return sum;}int times(int n, int m) {return (int) ((long) n * m % MOD);}int divide(int n, int m) {return times(n, IntMath.pow(m, MOD - 2, MOD));}int[] fact, invf;void calc(int len) {len += 2;fact = new int[len];invf = new int[len];fact[0] = fact[1] = invf[0] = invf[1] = 1;for (int i = 2; i < fact.length; ++i) fact[i] = times(fact[i - 1], i);invf[len - 1] = divide(1, fact[len - 1]);for (int i = len - 1; i > 1; --i) invf[i - 1] = times(i, invf[i]);}int comb(int n, int m) {if (n < m) return 0;return times(fact[n], times(invf[n - m], invf[m]));}}class FastScanner {private final java.io.InputStream in = System.in;private final byte[] buffer = new byte[8192];private int ptr = 0;private int buflen = 0;private boolean hasNextByte() {if (ptr < buflen) return true;ptr = 0;try {buflen = in.read(buffer);} catch (java.io.IOException e) {e.printStackTrace();}return buflen > 0;}private byte readByte() {return hasNextByte() ? buffer[ptr++] : -1;}private static boolean isPrintableChar(byte c) {return 32 < c || c < 0;}private static boolean isNumber(int c) {return '0' <= c && c <= '9';}public boolean hasNext() {while (hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++;return hasNextByte();}public String next() {if (!hasNext()) throw new java.util.NoSuchElementException();StringBuilder sb = new StringBuilder();byte b;while (isPrintableChar(b = readByte())) sb.appendCodePoint(b);return sb.toString();}public final char nextChar() {if (!hasNext()) throw new java.util.NoSuchElementException();return (char) readByte();}public final long nextLong() {if (!hasNext()) throw new java.util.NoSuchElementException();long n = 0;try {byte b = readByte();if (b == '-') {while (isNumber(b = readByte())) n = n * 10 + '0' - b;return n;} else if (!isNumber(b)) throw new NumberFormatException();do n = n * 10 + b - '0'; while (isNumber(b = readByte()));} catch (java.util.NoSuchElementException e) {}return n;}public final int nextInt() {if (!hasNext()) throw new java.util.NoSuchElementException();int n = 0;try {byte b = readByte();if (b == '-') {while (isNumber(b = readByte())) n = n * 10 + '0' - b;return n;} else if (!isNumber(b)) throw new NumberFormatException();do n = n * 10 + b - '0'; while (isNumber(b = readByte()));} catch (java.util.NoSuchElementException e) {}return n;}public double nextDouble() {return Double.parseDouble(next());}}class Arrays {public static void sort(final int[] array) {sort(array, 0, array.length);}public static void sort(final int[] array, int fromIndex, int toIndex) {if (toIndex - fromIndex <= 512) {java.util.Arrays.sort(array, fromIndex, toIndex);return;}sort(array, fromIndex, toIndex, 0, new int[array.length]);}private static final void sort(int[] a, final int from, final int to, final int l, final int[] bucket) {if (to - from <= 512) {java.util.Arrays.sort(a, from, to);return;}final int BUCKET_SIZE = 256;final int INT_RECURSION = 4;final int MASK = 0xff;final int shift = l << 3;final int[] cnt = new int[BUCKET_SIZE + 1];final int[] put = new int[BUCKET_SIZE];for (int i = from; i < to; i++) ++cnt[(a[i] >>> shift & MASK) + 1];for (int i = 0; i < BUCKET_SIZE; i++) cnt[i + 1] += cnt[i];for (int i = from; i < to; i++) {int bi = a[i] >>> shift & MASK;bucket[cnt[bi] + put[bi]++] = a[i];}for (int i = BUCKET_SIZE - 1, idx = from; i >= 0; i--) {int begin = cnt[i];int len = cnt[i + 1] - begin;System.arraycopy(bucket, begin, a, idx, len);idx += len;}final int nxtL = l + 1;if (nxtL < INT_RECURSION) {sort(a, from, to, nxtL, bucket);if (l == 0) {int lft, rgt;lft = from - 1;rgt = to;while (rgt - lft > 1) {int mid = lft + rgt >> 1;if (a[mid] < 0) lft = mid;else rgt = mid;}reverse(a, from, rgt);reverse(a, rgt, to);}}}public static void sort(final long[] array) {sort(array, 0, array.length);}public static void sort(final long[] array, int fromIndex, int toIndex) {if (toIndex - fromIndex <= 512) {java.util.Arrays.sort(array, fromIndex, toIndex);return;}sort(array, fromIndex, toIndex, 0, new long[array.length]);}private static final void sort(long[] a, final int from, final int to, final int l, final long[] bucket) {final int BUCKET_SIZE = 256;final int LONG_RECURSION = 8;final int MASK = 0xff;final int shift = l << 3;final int[] cnt = new int[BUCKET_SIZE + 1];final int[] put = new int[BUCKET_SIZE];for (int i = from; i < to; i++) ++cnt[(int) ((a[i] >>> shift & MASK) + 1)];for (int i = 0; i < BUCKET_SIZE; i++) cnt[i + 1] += cnt[i];for (int i = from; i < to; i++) {int bi = (int) (a[i] >>> shift & MASK);bucket[cnt[bi] + put[bi]++] = a[i];}for (int i = BUCKET_SIZE - 1, idx = from; i >= 0; i--) {int begin = cnt[i];int len = cnt[i + 1] - begin;System.arraycopy(bucket, begin, a, idx, len);idx += len;}final int nxtL = l + 1;if (nxtL < LONG_RECURSION) {sort(a, from, to, nxtL, bucket);if (l == 0) {int lft, rgt;lft = from - 1;rgt = to;while (rgt - lft > 1) {int mid = lft + rgt >> 1;if (a[mid] < 0) lft = mid;else rgt = mid;}reverse(a, from, rgt);reverse(a, rgt, to);}}}public static void reverse(int[] array) {reverse(array, 0, array.length);}public static void reverse(int[] array, int fromIndex, int toIndex) {for (--toIndex; fromIndex < toIndex; ++fromIndex, --toIndex) {int swap = array[fromIndex];array[fromIndex] = array[toIndex];array[toIndex] = swap;}}public static void reverse(long[] array) {reverse(array, 0, array.length);}public static void reverse(long[] array, int fromIndex, int toIndex) {for (--toIndex; fromIndex < toIndex; ++fromIndex, --toIndex) {long swap = array[fromIndex];array[fromIndex] = array[toIndex];array[toIndex] = swap;}}public static void shuffle(int[] array) {java.util.Random rnd = new java.util.Random();for (int i = 0; i < array.length; ++i) {int j = rnd.nextInt(array.length - i) + i;int swap = array[i];array[i] = array[j];array[j] = swap;}}public static void shuffle(long[] array) {java.util.Random rnd = new java.util.Random();for (int i = 0; i < array.length; ++i) {int j = rnd.nextInt(array.length - i) + i;long swap = array[i];array[i] = array[j];array[j] = swap;}}}class IntMath {public static int gcd(int a, int b) {while (a != 0) if ((b %= a) != 0) a %= b;else return a;return b;}public static int gcd(int... array) {int ret = array[0];for (int i = 1; i < array.length; ++i) ret = gcd(ret, array[i]);return ret;}public static long gcd(long a, long b) {while (a != 0) if ((b %= a) != 0) a %= b;else return a;return b;}public static long gcd(long... array) {long ret = array[0];for (int i = 1; i < array.length; ++i) ret = gcd(ret, array[i]);return ret;}public static long lcm(long a, long b) {return a / gcd(a, b) * b;}public static int pow(int a, int b) {int ans = 1;for (int mul = a; b > 0; b >>= 1, mul *= mul) if ((b & 1) != 0) ans *= mul;return ans;}public static long pow(long a, long b) {long ans = 1;for (long mul = a; b > 0; b >>= 1, mul *= mul) if ((b & 1) != 0) ans *= mul;return ans;}public static int pow(int a, long b, int mod) {if (b < 0) b = b % (mod - 1) + mod - 1;long ans = 1;for (long mul = a; b > 0; b >>= 1, mul = mul * mul % mod) if ((b & 1) != 0) ans = ans * mul % mod;return (int) ans;}public static int pow(long a, long b, int mod) {return pow((int) (a % mod), b, mod);}public static int floorsqrt(long n) {return (int) Math.sqrt(n + 0.1);}public static int ceilsqrt(long n) {return n <= 1 ? (int) n : (int) Math.sqrt(n - 0.1) + 1;}}