CCC

#include<bits/stdc++.h>
#define int long long
#define Aqrfre(x, y) freopen(#x ".in", "r", stdin),freopen(#y ".out", "w", stdout)
#define th2 second
#define th1 first
#define mp make_pair
#define Type int
#define qr(x) x=read()
typedef long long ll;
using namespace std;

inline Type read(){
    char c=getchar(); Type x=0, f=1;
    while(!isdigit(c)) (c=='-'?f=-1:f=1), c=getchar();
    while(isdigit(c)) x=(x<<1)+(x<<3)+(c^48), c=getchar();
    return x*f;
}

const int N = 205;

int n, m, T, a[N];
priority_queue<int>s;

signed main(){ // a
    // Aqrfre(a, a);

    qr(T);

    for(int th=1; th<=T; th++){
        qr(n); qr(m);
        for(int i=1; i<=n; i++) qr(a[i]);
        sort(a+1, a+1+n);

        while(s.size()) s.pop();
        int ans = 0;
        for(int i=2; i<=n; i++){
            ans += a[i] - a[i-1];
            s.push(a[i] - a[i-1]);
        }
        int cnt = 0;
        while(s.size()){
            if(cnt == m - 1) break;
            ans -= s.top();
            cnt++; s.pop();
        }
        printf("Case #%lld: %lld\n", th, ans);
    }
    


    return 0;
}