#include<cstdio>
#include<cmath>
#include<algorithm>
using namespace std;
typedef long double ld;
const int N=65540;
const ld pi=acos(-1.0);
int T,C,_,P,n,m,a[N],i,j,pos[N],w[6];
struct comp{ld r,i;comp(ld _r=0,ld _i=0){r=_r,i=_i;}comp operator+(const comp&x){return comp(r+x.r,i+x.i);}comp operator-(const comp&x){return comp(r-x.r,i-x.i);}comp operator*(const comp&x){return comp(r*x.r-i*x.i,r*x.i+i*x.r);}
}f[6][N],g[N];
inline void FFT(comp*a,int n,int t){for(int i=1;i<n;i++)if(i<pos[i])swap(a[i],a[pos[i]]);for(int d=0;(1<<d)<n;d++){int m=1<<d,m2=m<<1;ld o=pi*2/m2*t;comp _w(cos(o),sin(o));for(int i=0;i<n;i+=m2){comp w(1,0);for(int j=0;j<m;j++){comp&A=a[i+j+m],&B=a[i+j],t=w*A;A=B-t;B=B+t;w=w*_w;}}}if(t==-1)for(int i=0;i<n;i++)a[i].r/=n;
}
void dfs(int x,int y){if(x==P){int i,j,k=(P-y)&1?-1:1;for(i=1;i<=y;i++)for(j=2;j<w[i];j++)k*=j;comp t(k,0);for(j=0;j<m;j++)g[j]=f[w[1]][j];for(i=2;i<=y;i++)for(j=0;j<m;j++)g[j]=g[j]*f[w[i]][j];for(j=0;j<m;j++)f[0][j]=f[0][j]+g[j]*t;return;}for(int i=1;i<=y+1;i++){w[i]++;dfs(x+1,max(i,y));w[i]--;}
}
int main(){scanf("%d",&T);while(T--){scanf("%d%d",&_,&P);for(n=i=0;i<_;i++){scanf("%d",&a[i]);if(a[i]>n)n=a[i];}n*=P;for(m=1;m<=n;m<<=1);j=__builtin_ctz(m)-1;for(i=0;i<m;i++)pos[i]=pos[i>>1]>>1|((i&1)<<j);for(i=0;i<=P;i++)for(j=0;j<m;j++)f[i][j]=comp(0,0);for(i=0;i<_;i++)for(j=1;j<=P;j++)f[j][j*a[i]].r+=1;for(i=1;i<=P;i++)FFT(f[i],m,1);dfs(0,0);FFT(f[0],m,-1);for(j=i=1;i<=P;i++)j*=i;printf("Case #%d:\n",++C);for(i=1;i<m;i++){ld ans=f[0][i].r/j;if(ans>0.5)printf("%d: %.0f\n",i,(double)ans);}puts("");}return 0;
}