The main idea of the topic
Give you a tree with n points. And you have an integer k.
Let S be a set of points on a tree, and define f(S) as the smallest connected subgraph containing S.
In the k-point total (n k) scheme of N-point selection, please find out the f(S) and mod924844033 of all the schemes.
The author thinks it's too easy. He decides to ask you to find all k=1... The answer to n.
n≤200000
Title Solution
It seems that there is no way to find the answer quickly for each k.
Let's consider the contribution of one point to all the answers.
A point x is in this connected subgraph if and when the k points are not in the subtree of X when x is the root.
Then the contribution is (nk)(aik), where ai is the size of each subtree when x is the root. It can be found that the subtree size at both ends of each side is calculated once when calculating the total contribution. (nk) is calculated n times.
Set up
Where numi is the number of subtrees of size i
This can be converted into convolution.
Time complexity: O(nlogn)
Code
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cstdlib>
#include<ctime>
#include<utility>
#include<list>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
const ll p=924844033;
const ll g=5;
ll fp(ll a,ll b)
{
ll s=1;
while(b)
{
if(b&1)
s=s*a%p;
a=a*a%p;
b>>=1;
}
return s;
}
namespace ntt
{
ll w1[1000010];
ll w2[1000010];
int rev[1000010];
int n;
void init()
{
#ifdef DEBUG
n=16;
#else
n=524288;
#endif
int i;
for(i=1;i<=n;i<<=1)
{
w1[i]=fp(g,(p-1)/i);
w2[i]=fp(w1[i],p-2);
}
rev[0]=0;
for(i=1;i<n;i++)
rev[i]=(rev[i>>1]>>1)|(i&1?n>>1:0);
}
void ntt(ll *a,int t)
{
int i,j,k;
ll u,v,w,wn;
for(i=0;i<n;i++)
if(rev[i]<i)
swap(a[i],a[rev[i]]);
for(i=2;i<=n;i<<=1)
{
wn=(t==1?w1[i]:w2[i]);
for(j=0;j<n;j+=i)
{
w=1;
for(k=j;k<j+i/2;k++)
{
u=a[k];
v=a[k+i/2]*w%p;
a[k]=(u+v)%p;
a[k+i/2]=(u-v)%p;
w=w*wn%p;
}
}
}
if(t==-1)
{
ll inv=fp(n,p-2);
for(i=0;i<n;i++)
a[i]=a[i]*inv%p;
}
}
};
ll b[1000010];
ll c[1000010];
ll a[1000010];
ll inv[1000010];
ll fac[1000010];
ll ifac[1000010];
int s[1000010];
int n;
list<int> l[200010];
ll num[1000010];
void dfs(int x,int fa)
{
s[x]=1;
for(auto v:l[x])
if(v!=fa)
{
dfs(v,x);
s[x]+=s[v];
num[s[v]]--;
num[n-s[v]]--;
}
}
int main()
{
#ifdef DEBUG
freopen("b.in","r",stdin);
freopen("b.out","w",stdout);
#endif
scanf("%d",&n);
int i,x,y;
for(i=1;i<=n-1;i++)
{
scanf("%d%d",&x,&y);
l[x].push_back(y);
l[y].push_back(x);
}
inv[0]=inv[1]=fac[0]=fac[1]=ifac[0]=ifac[1]=1;
for(i=2;i<=n;i++)
{
inv[i]=-(p/i)*inv[p%i]%p;
fac[i]=fac[i-1]*i%p;
ifac[i]=ifac[i-1]*inv[i]%p;
}
dfs(1,0);
num[n]=n;
for(i=0;i<=n;i++)
b[i]=num[n-i]*fac[n-i]%p;
for(i=0;i<=n;i++)
c[i]=ifac[i];
ntt::init();
ntt::ntt(b,1);
ntt::ntt(c,1);
for(i=0;i<ntt::n;i++)
a[i]=b[i]*c[i]%p;
ntt::ntt(a,-1);
for(i=1;i<=n;i++)
{
ll ans=a[n-i]*ifac[i]%p;
ans=(ans+p)%p;
printf("%lld\n",ans);
}
return 0;
}