#868499 (Go) No.2299 Antitypoglycemia

• 問題: No.2299 Antitypoglycemia
• ユーザー: ynm3n
• 提出日時: 2023-05-12 21:36:22
• 言語: Go (1.22.1)
• 結果: AC
• 実行時間: 14 ms / 2,000 ms
• コード長: 5,046 bytes
• コンパイル時間: 15,381 ms
• コンパイル使用メモリ: 223,220 KB
• 実行使用メモリ: 5,376 KB
• 最終ジャッジ日時: 2024-05-06 11:18:37
• 合計ジャッジ時間: 13,208 ms
• ジャッジサーバーID （参考情報）: judge3 / judge5

入力	結果	実行時間; 実行使用メモリ
testcase_00	AC	1 ms; 5,248 KB
testcase_01	AC	1 ms; 5,248 KB
testcase_02	AC	1 ms; 5,248 KB
testcase_03	AC	9 ms; 5,376 KB
testcase_04	AC	9 ms; 5,376 KB
testcase_05	AC	5 ms; 5,376 KB
testcase_06	AC	9 ms; 5,376 KB
testcase_07	AC	3 ms; 5,376 KB
testcase_08	AC	8 ms; 5,376 KB
testcase_09	AC	9 ms; 5,376 KB
testcase_10	AC	4 ms; 5,376 KB
testcase_11	AC	4 ms; 5,376 KB
testcase_12	AC	11 ms; 5,376 KB
testcase_13	AC	13 ms; 5,376 KB
testcase_14	AC	3 ms; 5,376 KB
testcase_15	AC	2 ms; 5,376 KB
testcase_16	AC	5 ms; 5,376 KB
testcase_17	AC	4 ms; 5,376 KB
testcase_18	AC	10 ms; 5,376 KB
testcase_19	AC	10 ms; 5,376 KB
testcase_20	AC	14 ms; 5,376 KB
testcase_21	AC	14 ms; 5,376 KB
testcase_22	AC	11 ms; 5,376 KB
testcase_23	AC	2 ms; 5,376 KB
testcase_24	AC	1 ms; 5,376 KB
testcase_25	AC	1 ms; 5,376 KB
testcase_26	AC	1 ms; 5,376 KB
testcase_27	AC	1 ms; 5,376 KB

ソースコード

package main

import (
	"bufio"
	"fmt"
	"math"
	"math/big"
	"os"
	"strconv"
)

// 解答欄
func solve(sc *myScanner, wr *myWriter) {
	m := newModulus(998244353)
	n, a, b := sc.getInt3()

	fac := func(n int) int {
		res := 1
		for i := 1; i <= n; i++ {
			res = m.mul(res, i)
		}
		return res
	}

	ans := fac(n)
	ans = m.sub(ans, fac(n-1))
	ans = m.sub(ans, fac(n-1))
	if a != b {
		ans = m.add(ans, fac(n-2))
	}
	wr.println(ans)
}

// modulo tools
type modulus int

const defaultModP = int(1e9) + 7

func newModulus(p int) *modulus {
	m := modulus(p)
	return &m
}
func (m *modulus) mod(a int) int {
	if a < 0 || a >= int(*m) {
		a %= int(*m)
	}
	if a < 0 {
		a += int(*m)
	}
	return a
}
func (m *modulus) add(a, b int) int { return m.mod(a + b) }
func (m *modulus) sub(a, b int) int { return m.mod(a - b) }
func (m *modulus) mul(a, b int) int { return m.mod(a * b) }
func (m *modulus) div(a, b int) int { return m.mul(a, m.inv(b)) }
func (m *modulus) inv(a int) int {
	x, _ := extGcd(a, int(*m))
	return x
}
func (m *modulus) pow(a, n int) int {
	res := 1
	b := m.mod(a)
	for n > 0 {
		if n&1 > 0 {
			res = m.mul(res, b)
		}
		n >>= 1
		b = m.mul(b, b)
	}
	return res
}

func extGcd(a, b int) (int, int) {
	x0, y0 := 1, 0
	x1, y1 := 0, 1
	for a%b != 0 {
		q := a / b
		r := a % b
		x2, y2 := x0-q*x1, y0-q*y1

		a, b = b, r
		x0, y0 = x1, y1
		x1, y1 = x2, y2
	}
	return x1, y1
}

// 入出力の準備(sc, wr)
func main() {
	sc := &myScanner{bufio.NewScanner(os.Stdin)}
	wr := &myWriter{bufio.NewWriter(os.Stdout)}
	startBufSize := 4096
	maxBufSize := math.MaxInt64
	sc.Buffer(make([]byte, startBufSize), maxBufSize)
	sc.Split(bufio.ScanWords)

	solve(sc, wr)
	wr.Flush()
}

// useful funcs for slice
func makeInts(n, x int) []int {
	res := make([]int, n)
	for i := range res {
		res[i] = x
	}
	return res
}
func makeBools(n int, b bool) []bool {
	res := make([]bool, n)
	for i := range res {
		res[i] = b
	}
	return res
}
func countTrue(bs []bool) int {
	res := 0
	for _, b := range bs {
		if b {
			res++
		}
	}
	return res
}

// input
type myScanner struct {
	*bufio.Scanner
}

func (sc *myScanner) getInt() int {
	return sc._getIntOffset(0)
}
func (sc *myScanner) getInt2() (int, int) {
	return sc.getInt(), sc.getInt()
}
func (sc *myScanner) getInt3() (int, int, int) {
	return sc.getInt(), sc.getInt(), sc.getInt()
}
func (sc *myScanner) getInt4() (int, int, int, int) {
	return sc.getInt(), sc.getInt(), sc.getInt(), sc.getInt()
}
func (sc *myScanner) getInts(n int) []int {
	return sc._getIntsOffset(n, 0)
}
func (sc *myScanner) getIntZeroIndexed() int {
	return sc._getIntOffset(-1)
}
func (sc *myScanner) getIntsZeroIndexed(n int) []int {
	return sc._getIntsOffset(n, -1)
}
func (sc *myScanner) _getIntOffset(x int) int {
	res, err := strconv.Atoi(sc.getString())
	if err != nil {
		panic(err)
	}
	return res + x
}
func (sc *myScanner) _getIntsOffset(n, x int) []int {
	res := make([]int, n)
	for i := range res {
		res[i] = sc._getIntOffset(x)
	}
	return res
}
func (sc *myScanner) getString() string {
	sc.Scan()
	return sc.Text()
}
func (sc *myScanner) getStrings(n int) []string {
	res := make([]string, n)
	for i := range res {
		res[i] = sc.getString()
	}
	return res
}
func (sc *myScanner) getRunes() []rune {
	return []rune(sc.getString())
}
func (sc *myScanner) getFloat() float64 {
	res, err := strconv.ParseFloat(sc.getString(), 64)
	if err != nil {
		panic(err)
	}
	return res
}
func (sc *myScanner) getFloats(n int) []float64 {
	res := make([]float64, n)
	for i := range res {
		res[i] = sc.getFloat()
	}
	return res
}

// output
type myWriter struct {
	*bufio.Writer
}

func (wr *myWriter) println(a ...interface{}) {
	fmt.Fprintln(wr, a...)
}
func (wr *myWriter) printf(format string, a ...interface{}) {
	fmt.Fprintf(wr, format, a...)
}

// simple math funcs for int
func max(as ...int) int {
	res := as[0]
	for _, a := range as {
		if res < a {
			res = a
		}
	}
	return res
}
func min(as ...int) int {
	res := as[0]
	for _, a := range as {
		if res > a {
			res = a
		}
	}
	return res
}
func chMax(a *int, b int) {
	*a = max(*a, b)
}

func chMin(a *int, b int) {
	*a = min(*a, b)
}
func abs(a int) int {
	if a < 0 {
		return -a
	}
	return a
}
func pow(a, n int) int {
	res := 1
	b := a
	for n > 0 {
		if n&1 > 0 {
			res *= b
		}
		n >>= 1
		b *= b
	}
	return res
}
func sum(s ...int) int {
	res := 0
	for _, v := range s {
		res += v
	}
	return res
}
func checkPrime(a int) bool {
	if a == 2 {
		return true
	} else if a%2 == 0 {
		return false
	}
	res := true
	for q := 3; q*q <= a; q += 2 {
		if a%q == 0 {
			res = false
			break
		}
	}
	return res
}
func toBInt(a int) *big.Int {
	return big.NewInt(int64(a))
}

/*
	めも
	int(64)の最大値: 9223372036854775807 = (2^63 - 1)
	19桁
	10^18 < 2^60 < 2^63 < 10^19
	10^19 はintだとオーバーフローする

	sliceの長さ: 10^8程度までは許される
	型によるがそれ以上は Out of memory の危険がある

	1~nの和: {n*(n+1)}/2
	(1~nの平均値)*n を式変形したもの
	先に掛け算をすることで必ず2で割り切れる
*/