luoguP4921 情侣？给我烧了！ 组合数_容斥原理_计数问题

Code:

#include <cstdio>
#include <algorithm>
#include <cstring>
#define setIO(s) freopen(s".in","r",stdin),freopen(s".out","w",stdout)
#define mod 998244353
#define ll long long
#define maxn 2002 

using namespace std;

ll C[maxn][maxn],A[maxn][maxn],fac[maxn<<2],g[maxn],qpow[maxn<<2];
ll sum(int n,int k)
{
    if(k==0) return g[n];
    return ((((((C[n][k]*C[n][k])%mod)*fac[k])%mod)*qpow[k]%mod)*g[n-k]%mod);
}
void Init(){
    fac[1]=1,qpow[0]=1,g[0]=1;
    for(int i=1;i<=maxn*2;++i) qpow[i]=(qpow[i-1]<<1) % mod;
    for(int i=2;i<=maxn*2;++i) fac[i]=(fac[i-1]*i)%mod;
    for(int i=0;i<maxn;++i) C[i][i]=C[i][0]=1;
    for(int i=1;i<maxn;++i)
        for(int j=1;j<i;++j)
        {
            C[i][j]=(C[i-1][j]+C[i-1][j-1])%mod;
        }
    for(int i=1;i<maxn;++i)
    {
        g[i] = fac[i<<1];
        for(int j=1;j<=i;++j)
        {
            g[i]-=sum(i,j),g[i]=(g[i]+mod)%mod;
        }
    }
}
int main(){
    setIO("input");
    Init();
    int T;
    scanf("%d",&T);
    while(T--){
        int n;
        scanf("%d",&n);
        for(int i=0;i<=n;++i) printf("%lld\n",(sum(n,i)+mod)%mod);
    }
    return 0;
}