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#include <algorithm>
#include <iostream>
#include <utility>
#include <vector>
using namespace std;
const long long INF = 1LL << 60;
using Pt = pair<long long, long long>;
#define x first
#define y second
long long cross(const Pt &a, const Pt &b, const Pt &o = Pt(0, 0)) {
return (a.x - o.x) * (b.y - o.y) - (a.y - o.y) * (b.x - o.x);
}
template <class It>
vector<Pt> convex_hull(It lo, It hi) {
int k = 0;
if (hi - lo <= 1) {
return vector<Pt>(lo, hi);
}
vector<Pt> res(2 * distance(lo, hi));
sort(lo, hi);
for (It it = lo; it != hi; ++it) {
while (k >= 2 && cross(res[k - 1], *it, res[k - 2]) >= 0) {
k--;
}
res[k++] = *it;
}
int t = k + 1;
for (It it = hi - 2; it != lo - 1; --it) {
while (k >= t && cross(res[k - 1], *it, res[k - 2]) >= 0) {
k--;
}
res[k++] = *it;
}
res.resize(k - 1);
return res;
}
int N;
long long K, D;
long long solve() {
cin >> N >> K >> D;
vector<Pt> P(N);
for (int i = 0; i < N; i++) {
cin >> P[i].x >> P[i].y;
}
auto hull = convex_hull(P.begin(), P.end());
int V = hull.size();
// Find start/end.
int start = -1, dest = -1;
for (int i = 0; i < V; i++) {
if (hull[i] == P[0]) {
start = i;
} else if (hull[i] == P[N - 1]) {
dest = i;
}
}
// Dijkstra in O(V^2) time / O(V) space.
vector<bool> vis(V);
vector<long long> dist(V, INF);
dist[start] = 0;
while (true) {
int u = -1;
long long mindist = INF;
for (int i = 0; i < V; i++) {
if (!vis[i] && mindist > dist[i]) {
u = i;
mindist = dist[i];
}
}
if (mindist == INF || u == dest) {
break;
}
vis[u] = true;
for (int v = 0; v < V; v++) {
long long d = (hull[u].x - hull[v].x) * (hull[u].x - hull[v].x) +
(hull[u].y - hull[v].y) * (hull[u].y - hull[v].y);
if (!vis[v] && d <= D*D && dist[v] > dist[u] + max(K, d)) {
dist[v] = dist[u] + max(K, d);
}
}
}
return dist[dest] < INF ? dist[dest] : -1;
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
int T;
cin >> T;
for (int t = 1; t <= T; t++) {
cout << "Case #" << t << ": " << solve() << endl;
}
return 0;
}
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