結果

問題 No.1887 K Consecutive Ks (Easy)
ユーザー miscalc
提出日時 2022-03-06 17:30:55
言語 PyPy3
(7.3.15)
結果
AC  
実行時間 259 ms / 2,000 ms
コード長 5,323 bytes
コンパイル時間 395 ms
コンパイル使用メモリ 81,792 KB
実行使用メモリ 78,288 KB
最終ジャッジ日時 2024-07-21 03:18:43
合計ジャッジ時間 3,884 ms
ジャッジサーバーID
（参考情報） 		judge3 / judge2
このコードへのチャレンジ
（要ログイン）
ファイルパターン 結果
sample AC * 3
other AC * 16
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 #
プレゼンテーションモードにする

# ACL-for-python by shakayami
# https://github.com/shakayami/ACL-for-python/blob/master/convolution.py
class FFT():
    def primitive_root_constexpr(self,m):
        if m==2:return 1
        if m==167772161:return 3
        if m==469762049:return 3
        if m==754974721:return 11
        if m==998244353:return 3
        divs=[0]*20
        divs[0]=2
        cnt=1
        x=(m-1)//2
        while(x%2==0):x//=2
        i=3
        while(i*i<=x):
            if (x%i==0):
                divs[cnt]=i
                cnt+=1
                while(x%i==0):
                    x//=i
            i+=2
        if x>1:
            divs[cnt]=x
            cnt+=1
        g=2
        while(1):
            ok=True
            for i in range(cnt):
                if pow(g,(m-1)//divs[i],m)==1:
                    ok=False
                    break
            if ok:
                return g
            g+=1
    def bsf(self,x):
        res=0
        while(x%2==0):
            res+=1
            x//=2
        return res
    butterfly_first=True
    butterfly_inv_first=True
    sum_e=[0]*30
    sum_ie=[0]*30
    def __init__(self,MOD):
        self.mod=MOD
        self.g=self.primitive_root_constexpr(self.mod)
    def butterfly(self,a):
        n=len(a)
        h=(n-1).bit_length()
        if self.butterfly_first:
            self.butterfly_first=False
            es=[0]*30
            ies=[0]*30
            cnt2=self.bsf(self.mod-1)
            e=pow(self.g,(self.mod-1)>>cnt2,self.mod)
            ie=pow(e,self.mod-2,self.mod)
            for i in range(cnt2,1,-1):
                es[i-2]=e
                ies[i-2]=ie
                e=(e*e)%self.mod
                ie=(ie*ie)%self.mod
            now=1
            for i in range(cnt2-2):
                self.sum_e[i]=((es[i]*now)%self.mod)
                now*=ies[i]
                now%=self.mod
        for ph in range(1,h+1):
            w=1<<(ph-1)
            p=1<<(h-ph)
            now=1
            for s in range(w):
                offset=s<<(h-ph+1)
                for i in range(p):
                    l=a[i+offset]
                    r=a[i+offset+p]*now
                    r%=self.mod
                    a[i+offset]=l+r
                    a[i+offset]%=self.mod
                    a[i+offset+p]=l-r
                    a[i+offset+p]%=self.mod
                now*=self.sum_e[(~s & -~s).bit_length()-1]
                now%=self.mod
    def butterfly_inv(self,a):
        n=len(a)
        h=(n-1).bit_length()
        if self.butterfly_inv_first:
            self.butterfly_inv_first=False
            es=[0]*30
            ies=[0]*30
            cnt2=self.bsf(self.mod-1)
            e=pow(self.g,(self.mod-1)>>cnt2,self.mod)
            ie=pow(e,self.mod-2,self.mod)
            for i in range(cnt2,1,-1):
                es[i-2]=e
                ies[i-2]=ie
                e=(e*e)%self.mod
                ie=(ie*ie)%self.mod
            now=1
            for i in range(cnt2-2):
                self.sum_ie[i]=((ies[i]*now)%self.mod)
                now*=es[i]
                now%=self.mod
        for ph in range(h,0,-1):
            w=1<<(ph-1)
            p=1<<(h-ph)
            inow=1
            for s in range(w):
                offset=s<<(h-ph+1)
                for i in range(p):
                    l=a[i+offset]
                    r=a[i+offset+p]
                    a[i+offset]=l+r
                    a[i+offset]%=self.mod
                    a[i+offset+p]=(l-r)*inow
                    a[i+offset+p]%=self.mod
                inow*=self.sum_ie[(~s & -~s).bit_length()-1]
                inow%=self.mod
    def convolution(self,a,b):
        n=len(a);m=len(b)
        if not(a) or not(b):
            return []
        if min(n,m)<=40:
            if n<m:
                n,m=m,n
                a,b=b,a
            res=[0]*(n+m-1)
            for i in range(n):
                for j in range(m):
                    res[i+j]+=a[i]*b[j]
                    res[i+j]%=self.mod
            return res
        z=1<<((n+m-2).bit_length())
        a=a+[0]*(z-n)
        b=b+[0]*(z-m)
        self.butterfly(a)
        self.butterfly(b)
        c=[0]*z
        for i in range(z):
            c[i]=(a[i]*b[i])%self.mod
        self.butterfly_inv(c)
        iz=pow(z,self.mod-2,self.mod)
        for i in range(n+m-1):
            c[i]=(c[i]*iz)%self.mod
        return c[:n+m-1]
mod = 998244353
CONV = FFT(mod)
n, m = map(int, input().split())
d = [0] * (n + 10)
for i in range(2, m + 1):
  k = 1
  while k * i <= n:
    d[k * i - 1] += 1
    k += 1
pw = [0] * (n + 10)
pw[1], pw[2] = 1, m - 2
for i in range(2, n):
  pw[i + 1] = (m - 1) * pw[i] % mod
dp1 = [0] * (n + 10)
dp2 = [1] * (n + 10)
for i in range(n):
  dp2[i + 1] = (m - 1) * dp2[i] % mod
def onlineconvolution(l, r):
  if l + 1 == r:
    return
  c = (l + r) // 2
  onlineconvolution(l, c)
  dp20 = dp2[l : c]
  d0 = d[: r - l]
  r1 = CONV.convolution(dp20, d0)
  for i in range(c, r):
    dp1[i] += r1[i - l]
    if dp1[i] >= mod:
      dp1[i] -= mod
  dp10 = dp1[l : c]
  pw0 = pw[: r - l]
  r2 = CONV.convolution(dp10, pw0)
  for i in range(c, r):
    dp2[i] += mod - r2[i - l]
    if dp2[i] >= mod:
      dp2[i] -= mod
  onlineconvolution(c, r)
onlineconvolution(0, n + 1)
ans = pow(m, n, mod) + mod - dp2[n]
if ans >= mod:
  ans -= mod
print(ans)
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
0