結果
問題 | No.1300 Sum of Inversions |
ユーザー |
![]() |
提出日時 | 2020-11-28 18:45:11 |
言語 | Go (1.23.4) |
結果 |
AC
|
実行時間 | 558 ms / 2,000 ms |
コード長 | 5,705 bytes |
コンパイル時間 | 16,759 ms |
コンパイル使用メモリ | 230,264 KB |
実行使用メモリ | 11,860 KB |
最終ジャッジ日時 | 2024-09-12 23:22:25 |
合計ジャッジ時間 | 25,686 ms |
ジャッジサーバーID (参考情報) |
judge3 / judge4 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 34 |
ソースコード
package mainimport ("bufio""fmt""os""sort""strconv")var sc = bufio.NewScanner(os.Stdin)var wr = bufio.NewWriter(os.Stdout)func out(x ...interface{}) {fmt.Fprintln(wr, x...)}func getI() int {sc.Scan()i, e := strconv.Atoi(sc.Text())if e != nil {panic(e)}return i}func getF() float64 {sc.Scan()i, e := strconv.ParseFloat(sc.Text(), 64)if e != nil {panic(e)}return i}func getInts(N int) []int {ret := make([]int, N)for i := 0; i < N; i++ {ret[i] = getI()}return ret}func getS() string {sc.Scan()return sc.Text()}// min, max, asub, absなど基本関数func max(a, b int) int {if a > b {return a}return b}func min(a, b int) int {if a < b {return a}return b}func asub(a, b int) int {if a > b {return a - b}return b - a}func abs(a int) int {if a >= 0 {return a}return -a}func lowerBound(a []int, x int) int {idx := sort.Search(len(a), func(i int) bool {return a[i] >= x})return idx}func upperBound(a []int, x int) int {idx := sort.Search(len(a), func(i int) bool {return a[i] > x})return idx}//----------------------------------------// modint//----------------------------------------type modint struct {mod intfracMemo []intifracMemo []int}func newModint(m int) *modint {var ret modintret.mod = mret.fracMemo = []int{1, 1}ret.ifracMemo = []int{1, 1}return &ret}func (m *modint) add(a, b int) int {ret := (a + b) % m.modif ret < 0 {ret += m.mod}return ret}func (m *modint) sub(a, b int) int {ret := (a - b) % m.modif ret < 0 {ret += m.mod}return ret}func (m *modint) mul(a, b int) int {ret := a * b % m.modif ret < 0 {ret += m.mod}return ret}func (m *modint) div(a, b int) int {ret := a * m.modinv(b)ret %= m.modreturn ret}func (m *modint) pow(p, n int) int {ret := 1x := pfor n != 0 {if n%2 == 1 {ret *= xret %= m.mod}n /= 2x = x * x % m.mod}return ret}// 逆元を使った割り算(MOD)// mod. m での a の逆元 a^{-1} を計算するfunc (m *modint) modinv(a int) int {b := m.modu := 1v := 0for b != 0 {t := a / ba -= t * ba, b = b, au -= t * vu, v = v, u}u %= m.modif u < 0 {u += m.mod}return u}//-----------------------------------------------// 行列累乗// A[][]のp乗を求める//-----------------------------------------------func (m *modint) powModMatrix(A [][]int, p int) [][]int {N := len(A)ret := make([][]int, N)for i := 0; i < N; i++ {ret[i] = make([]int, N)ret[i][i] = 1}for p > 0 {if p&1 == 1 {ret = m.mulMod(ret, A)}A = m.mulMod(A, A)p >>= 1}return ret}func (m *modint) mulMod(A, B [][]int) [][]int {H := len(A)W := len(B[0])K := len(A[0])C := make([][]int, W)for i := 0; i < W; i++ {C[i] = make([]int, W)}for i := 0; i < H; i++ {for j := 0; j < W; j++ {for k := 0; k < K; k++ {C[i][j] += A[i][k] * B[k][j]C[i][j] %= m.mod}}}return C}//---------------------------------------------------// nCk 計算関連: TELすることがあるかも// ※pow(x, p-2)を何度も取るので// 厳しそうな場合は、ここを削除して高速なのを使う//---------------------------------------------------func (m *modint) mfrac(n int) int {if len(m.fracMemo) > n {return m.fracMemo[n]}if len(m.fracMemo) == 0 {m.fracMemo = append(m.fracMemo, 1)}for len(m.fracMemo) <= n {size := len(m.fracMemo)m.fracMemo = append(m.fracMemo, m.fracMemo[size-1]*size%m.mod)}return m.fracMemo[n]}func (m *modint) mifrac(n int) int {if len(m.ifracMemo) > n {return m.ifracMemo[n]}if len(m.ifracMemo) == 0 {m.fracMemo = append(m.ifracMemo, 1)}for len(m.ifracMemo) <= n {size := len(m.ifracMemo)m.ifracMemo = append(m.ifracMemo, m.ifracMemo[size-1]*m.pow(size, m.mod-2)%m.mod)}return m.ifracMemo[n]}func (m *modint) nCr(n, r int) int {if n == r {return 1}if n < r || r < 0 {return 0}ret := 1ret *= m.mfrac(n)ret %= m.modret *= m.mifrac(r)ret %= m.modret *= m.mifrac(n - r)ret %= m.modreturn (ret)}type BIT struct {v []int}func newBIT(n int) *BIT {b := new(BIT)b.v = make([]int, n)return b}func (b BIT) sum(a int) int {ret := 0for i := a + 1; i > 0; i -= i & -i {ret += b.v[i-1]ret %= mod.mod}return ret}func (b BIT) rangeSum(x, y int) int {if y == 0 {return 0}y--if x == 0 {return b.sum(y)} else {return b.sum(y) - b.sum(x-1)}}func (b BIT) add(a, w int) {n := len(b.v)for i := a + 1; i <= n; i += i & -i {b.v[i-1] += wb.v[i-1] %= mod.mod}}type obj struct {a, i int}var mod = newModint(998244353)func main() {defer wr.Flush()sc.Split(bufio.ScanWords)sc.Buffer([]byte{}, 1000000)// this template is new version.// use getI(), getS(), getInts(), getF()N := getI()a := getInts(N)b := make([]obj, N)for i := 0; i < N; i++ {b[i] = obj{a[i], i + 1}}sort.Slice(b, func(i, j int) bool {if b[i].a == b[j].a {return b[i].i < b[j].i}return b[i].a < b[j].a})bit1 := newBIT(N + 1)bit1c := newBIT(N + 1)bit2 := newBIT(N + 1)bit2c := newBIT(N + 1)ans := 0for i := 0; i < N; i++ {o := b[i]v2 := mod.sub(bit2.sum(N), bit2.sum(o.i))c2 := mod.sub(bit2c.sum(N), bit2c.sum(o.i))val := mod.add(mod.mul(o.a, c2), v2)ans = mod.add(ans, val)v1 := mod.sub(bit1.sum(N), bit1.sum(o.i))c1 := mod.sub(bit1c.sum(N), bit1c.sum(o.i))p := mod.add(mod.mul(o.a, c1), v1)bit2.add(o.i, p)bit2c.add(o.i, c1)bit1.add(o.i, o.a)bit1c.add(o.i, 1)}out(ans)}