#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstring>
using namespace std;
const int Mx=50010;
int n,k;
long double ans,tmp,sum,ave,a[Mx];
bool cmp(long double a,long double b) { return a<b; }
int main()
{int T; scanf("%d",&T);for(int t=1;t<=T;t++){printf("Case #%d:\n",t);tmp=0,sum=0;scanf("%d%d",&n,&k);for(int i=1;i<=n;i++) scanf("%LF",&a[i]);if(n==k) { cout<<"0.000000"<<endl; continue; }sort(a+1,a+1+n,cmp);for(int i=1;i<=n-k;i++) tmp+=a[i]*a[i],sum+=a[i];ave=sum/(n-k);ans=tmp-2*ave*sum+(n-k)*ave*ave;for(int l=1,r=n-k+1;r<=n;l++,r++){tmp+=a[r]*a[r]-a[l]*a[l];sum+=a[r]-a[l];ave=sum/(n-k);ans=min(ans,tmp-2*ave*sum+(n-k)*ave*ave);}printf("%.8LF\n",ans);}return 0;
}

#include <cstdio>
#include <cmath>
#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;
const int Mx=2010;
const long long p=1e9+7;
int n,cnt,pr[Mx],vis[Mx],tran[310][310];
void pre()
{for(int i=2;i<=2000;i++){int jud=1;for(int j=2;j*j<=i;j++)if(i%j==0) jud=0;if(jud) pr[++cnt]=i;}
}
long long power(long long a,long long b)
{long long c=1;while(b){if(b&1) c=c*a%p;a=a*a%p;b>>=1;}return c;
}
int gauss()
{int i=1;for(int j=1;i<=cnt&&j<=n;i++,j++){int tmp=i;for(int k=i+1;k<=cnt;k++)if(tran[k][j]>tran[tmp][j]) tmp=k;if(tmp!=i)for(int k=j;k<=n+1;k++) swap(tran[tmp][k],tran[i][k]);if(tran[i][j]==0) { i--; continue; }for(int k=i+1;k<=cnt;k++){if(!tran[k][j]) continue;for(int l=j;l<=n+1;l++)tran[k][l]=tran[k][l]^tran[i][l];}}return n-(i-1);
}
int main()
{pre();int T; scanf("%d",&T);for(int t=1;t<=T;t++){memset(tran,0,sizeof(tran));printf("Case #%d:\n",t);scanf("%d",&n);for(int i=1;i<=n;i++){long long x; scanf("%lld",&x);for(int j=1;j<=cnt;j++){int tot=0;while(x%pr[j]==0)x/=pr[j],tot++;tran[j][i]=tot&1;}}printf("%lld\n",(long long) power(2,gauss())-1);}return 0;
}

#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<iostream>
#include<algorithm>
using namespace std;const int N = 200010;
int to[N << 1], nxt[N << 1], head[N], cnt;
void add(int x, int y){to[++ cnt] = y; nxt[cnt] = head[x]; head[x] = cnt;to[++ cnt] = x; nxt[cnt] = head[y]; head[y] = cnt;
}struct Rec{int x1, x2, y1, y2, val;
}rec[N * 10];
struct Event{int l, r, y, val, rank;
}events[N * 10];
bool operator < (const Event &a, const Event &b){return a.y < b.y || (a.y == b.y && a.rank < b.rank);
}struct treasure{int key, chest, val;
}a[N];
int st[N], ed[N], n, m, dfs_clock, dep[N], fa[N][20];int LCA(int x, int y){if (dep[x] < dep[y]) swap(x, y);int t = dep[x] - dep[y];for(int i = 0; i < 20; i ++) if (t >> i & 1) x = fa[x][i];for(int i = 19; i >= 0; i --)if (fa[x][i] != fa[y][i]) x = fa[x][i], y = fa[y][i];if (x == y) return x;return fa[x][0];
}void dfs(int x){st[x] = ++ dfs_clock;for(int i = 1; (1 << i) <= dep[x]; i ++)fa[x][i] = fa[fa[x][i - 1]][i - 1];for(int i = head[x]; i; i = nxt[i])if (st[to[i]] == 0){dep[to[i]] = dep[x] + 1;fa[to[i]][0] = x;dfs(to[i]);}ed[x] = dfs_clock;
}struct node{int tag, max;
}t[N << 2];
#define mid ((l + r) >> 1)
#define L (o << 1)
#define R (o << 1 | 1)
#define lch L, l, mid
#define rch R, mid + 1, rvoid Push_up(int o){t[o].max = max(t[L].max, t[R].max);
}
void change(int o, int v){t[o].tag += v; t[o].max += v;
}
void Push_down(int o){if (t[o].tag){change(L, t[o].tag);change(R, t[o].tag);t[o].tag = 0;}
}
void update(int o, int l, int r, int ql, int qr, int v){if (ql > qr) return;if (ql <= l && qr >= r) change(o, v);else{Push_down(o);if (ql <= mid) update(lch, ql, qr, v);if (qr >  mid) update(rch, ql, qr, v);Push_up(o);}
}int main(){int T, cs = 0;scanf("%d", &T);while(cs < T){printf("Case #%d: ", ++ cs);memset(head, 0, sizeof head);memset(st, 0, sizeof st);memset(fa, 0, sizeof fa);memset(dep, 0, sizeof dep);memset(t, 0, sizeof t);cnt = dfs_clock = 0;scanf("%d%d", &n, &m);int x, y;for(int i = 1; i < n; i ++){scanf("%d%d", &x, &y);add(x, y);}dfs(1);
//        for(int i = 1; i <= n; i ++) printf("st[%d] = %d ed[%d] = %d\n", i, st[i], i, ed[i]);int tot = 0, num = 0, ans = 0, tmp = 0;for(int i = 1; i <= m; i ++){scanf("%d%d%d", &a[i].key, &a[i].chest, &a[i].val);int lca = LCA(a[i].key, a[i].chest);if (a[i].key == a[i].chest){tmp += a[i].val;for(int j = head[a[i].key]; j; j = nxt[j])if (to[j] != fa[a[i].key][0]){rec[++ tot] = (Rec){st[to[j]], ed[to[j]], st[to[j]], ed[to[j]], -a[i].val};}if (1 <= st[a[i].key] - 1 && ed[a[i].key] + 1 <= n){rec[++ tot] = (Rec){1, st[a[i].key] - 1, ed[a[i].key] + 1, n, -a[i].val};rec[++ tot] = (Rec){ed[a[i].key] + 1, n, 1, st[a[i].key] - 1, -a[i].val};}if (1 <= st[a[i].key] - 1)rec[++ tot] = (Rec){1, st[a[i].key] - 1, 1, st[a[i].key] - 1, -a[i].val};if (ed[a[i].key] + 1 <= n)rec[++ tot] = (Rec){ed[a[i].key] + 1, n, ed[a[i].key] + 1, n, -a[i].val};}else if (a[i].key == lca){for(int j = head[a[i].key]; j; j = nxt[j])if (to[j] != fa[a[i].key][0] && LCA(to[j], a[i].chest) == to[j]){y = to[j];break;}if (1 <= st[y] - 1) rec[++ tot] = (Rec){1, st[y] - 1, st[a[i].chest], ed[a[i].chest], a[i].val};if (ed[y] + 1 <= n) rec[++ tot] = (Rec){ed[y] + 1, n, st[a[i].chest], ed[a[i].chest], a[i].val};}else if (a[i].chest == lca){for(int j = head[a[i].chest]; j; j = nxt[j])if (to[j] != fa[a[i].chest][0] && LCA(to[j], a[i].key) == to[j]){y = to[j];break;}if (1 <= st[y] - 1) rec[++ tot] = (Rec){st[a[i].key], ed[a[i].key], 1, st[y] - 1, a[i].val};if (ed[y] + 1 <= n) rec[++ tot] = (Rec){st[a[i].key], ed[a[i].key], ed[y] + 1, n, a[i].val};}else{rec[++ tot] = (Rec){st[a[i].key], ed[a[i].key], st[a[i].chest], ed[a[i].chest], a[i].val};}
//            if (rec[tot].x1 == 0) printf("%d %d %d lca = %d\n", a[i].key, a[i].chest, a[i].val, lca);
        }
//        for(int i = 1; i <= tot; i ++)
//            printf("%d %d %d %d %d\n", rec[i].x1, rec[i].x2, rec[i].y1, rec[i].y2, rec[i].val);int tt = 0;for(int i = 1; i <= tot; i ++){
//            if (rec[i].x1 == 0 && rec[i].x2 == 0) printf("%d\n", ++ tt);events[++ num] = (Event){rec[i].x1, rec[i].x2, rec[i].y1, rec[i].val, 1};events[++ num] = (Event){rec[i].x1, rec[i].x2, rec[i].y2 + 1, -rec[i].val, 0};}sort(events + 1, events + num + 1);for(int i = 1; i <= num; i ++){if (events[i].y > events[i - 1].y || i == 1) ans = max(ans, t[1].max);update(1, 1, n, events[i].l, events[i].r, events[i].val);if (i == num) ans = max(ans, t[1].max);
//            printf("%d\n", t[1].max);
        }printf("%d\n", ans + tmp);}return 0;
}