1 //I-卡特兰数-组合数学-阶乘逆元快速幂

 2 #include<iostream>

 3 #include<cstring>

 4 #include<cstdio>

 5 #include<cmath>

 6 #include<cstdlib>

 7 #include<algorithm>

 8 #include<queue>

 9 #include<vector>

10 using namespace std;

11 typedef long long ll;

12 const int maxn=2*1e5+10;

13 const int mod=998244353;

14 ll f[maxn];

15 void ff(){

16     f[0]=1;

17     for(int i=1;i<maxn;i++)

18         f[i]=(i*f[i-1])%mod;

19 }

20 ll poww(ll n,ll m){   //快速幂

21     ll ans=1;

22     while(m){

23         if(m&1)ans=(ans*n)%mod;

24         m=m>>1;

25         n=(n*n)%mod;

26     }

27     return ans;

28 }

29 ll cc(ll n,ll m){      //组合数

30     ll ans=f[n];

31     ans=(ans*poww(f[m],mod-2))%mod;

32     ans=(ans*poww(f[n-m],mod-2))%mod;

33     return ans;

34 }

35 int main(){

36     int t,n,m,h=0;

37     ff();

38     cin>>t;

39     while(t--){

40         cin>>n;

41         m=n-1;

42         ll ans=(cc(2*n,n)-cc(2*n,n-1)-cc(2*m,m)+cc(2*m,m-1)+2*mod)%mod;

43         cout<<"Case #"<<++h<<": "<<ans<<endl;

44     }

45 }