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```/**
SHAMI AL BASHAR PROTHOY
PRESIDENCY INTERNATIONAL SCHOOL
**/

#include <bits/stdc++.h>
using namespace std;
#define csee "Case "<<cs<<": "
typedef long long ll;
typedef long double ld;
#define B begin()
#define E end()
#define F first
#define S second
#define pb push_back
#define pp pop_back
#define ins insert
#define vi vector
const ld pi=2*acos(0.0);
ll T,N;
ll cs=1;
ll soln=0;
/**
THINK TWICE,
CODE ONCE
**/
bool ok(vi<vi<ll>>&v,ll row,ll col)
{
if(row>=0&&row<N&&col>=0&&col<N&&!v[row][col])
return true;
return false;
}
void go(vi<vi<ll>>&v,ll row,ll col,ll tp)
{
if(row==N-1&&col==N-1)
{
if(N*N==tp)
soln++;
return;
}
v[row][col]=1;
if(row==0&&col==0)
go(v,row+1,col,tp+1);
else
{
v[row][col]=0;
bool l=false,r=false,u=false,d=false;
if(ok(v,row,col+1))
r=true;
if(ok(v,row,col-1))
l=true;
if(ok(v,row+1,col))
d=true;
if(ok(v,row-1,col))
u=true;
if(!u&&!d&&r&&l)
return;
if(u&&d&&!r&&!l)
return;
v[row][col]=1;
if(r)
go(v,row,col+1,tp+1);
if(l)
go(v,row,col-1,tp+1);
if(d)
go(v,row+1,col,tp+1);
if(u)
go(v,row-1,col,tp+1);
}
v[row][col]=0;
}
void sol(ll cs)
{
soln=0;
cin>>N;
vi<ll>temp(N,0);
vi<vi<ll>>v(N,temp);
go(v,0,0,1);
cout<<csee<<2*soln<<"\n";
}
//CODE
int main()
{
//freopen("inp.txt","r",stdin)
scanf("%lld",&T);
while(T--)
sol(cs++);
return 0;
}
```