結果

問題 No.2327 Inversion Sum
ユーザー CuriousFairy315CuriousFairy315
提出日時 2023-05-28 14:46:43
言語 Java21
(openjdk 21)
結果
AC  
実行時間 281 ms / 2,000 ms
コード長 11,323 bytes
コンパイル時間 2,513 ms
コンパイル使用メモリ 90,452 KB
実行使用メモリ 58,640 KB
最終ジャッジ日時 2023-08-27 10:34:20
合計ジャッジ時間 7,936 ms
ジャッジサーバーID
（参考情報） 		judge13 / judge12
このコードへのチャレンジ
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テストケース

テストケース表示
入力 結果 実行時間
実行使用メモリ
testcase_00 AC 144 ms
56,388 KB
testcase_01 AC 252 ms
57,876 KB
testcase_02 AC 248 ms
57,844 KB
testcase_03 AC 120 ms
55,460 KB
testcase_04 AC 260 ms
57,992 KB
testcase_05 AC 123 ms
55,420 KB
testcase_06 AC 238 ms
56,668 KB
testcase_07 AC 178 ms
55,204 KB
testcase_08 AC 107 ms
53,104 KB
testcase_09 AC 281 ms
58,004 KB
testcase_10 AC 147 ms
54,600 KB
testcase_11 AC 92 ms
55,140 KB
testcase_12 AC 74 ms
52,812 KB
testcase_13 AC 71 ms
51,556 KB
testcase_14 AC 220 ms
58,336 KB
testcase_15 AC 275 ms
58,640 KB
testcase_16 AC 200 ms
57,788 KB
testcase_17 AC 102 ms
55,136 KB
testcase_18 AC 104 ms
53,396 KB
testcase_19 AC 153 ms
56,308 KB
testcase_20 AC 52 ms
49,988 KB
testcase_21 AC 50 ms
50,072 KB
testcase_22 AC 50 ms
50,012 KB
testcase_23 AC 50 ms
50,140 KB
testcase_24 AC 49 ms
50,040 KB
testcase_25 AC 51 ms
50,028 KB
testcase_26 AC 51 ms
50,076 KB
testcase_27 AC 49 ms
50,444 KB
testcase_28 AC 50 ms
50,132 KB
testcase_29 AC 51 ms
50,164 KB
testcase_30 AC 51 ms
50,132 KB
testcase_31 AC 50 ms
50,020 KB
testcase_32 AC 53 ms
49,948 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 # 


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;
	}
}
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