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#include <algorithm>
#include <cstring>
#include <iostream>
#include <vector>
using namespace std;
const int LIM = 52;
inline int& setmax(int &l, int r) {
return l = max(l, r);
}
int N, K, C[LIM];
vector<int> adj[LIM];
// dp[i][j][k] = max value in i's subtree,
// with j new paths present,
// and with a free path ongoing from i's parent if k=1.
int dp[LIM][LIM][2];
// dp2[i][j][k][c] = max value after first i children of current node,
// with j new paths present,
// and with a free path available for use if k=1,
// and with at least one child connected if c=1.
int dp2[LIM][LIM][2][2];
void rec(int i, int parent) {
int nc = 0;
for (int j : adj[i]) {
if (j != parent) {
rec(j, i);
nc++;
}
}
// Sub-DP.
for (int j = 0; j <= nc; j++) {
memset(dp2[j], -1, sizeof dp2[j]);
}
dp2[0][0][0][0] = 0;
nc = 0;
for (int j : adj[i]) {
if (j == parent) {
continue;
}
for (int a1 = 0; a1 <= K; a1++) {
for (int x : {0, 1}) {
for (int y : {0, 1}) {
int d = dp2[nc][a1][x][y];
if (d < 0) {
continue;
}
for (int a2 = 0; a2 <= K - a1; a2++) {
// Connect to child.
int d2 = dp[j][a2][1];
if (d2 >= 0) {
setmax(dp2[nc + 1][a1 + a2 + (x ? 0 : 1)][1 - x][1], d + d2);
}
// Don't connect to child.
d2 = dp[j][a2][0];
if (d2 >= 0) {
setmax(dp2[nc + 1][a1 + a2][x][y], d + d2);
}
}
}
}
}
nc++;
}
// Combine into main DP.
memset(dp[i], -1, sizeof dp[i]);
for (int o : {0, 1}) {
for (int j = 0; j <= K; j++) {
for (int x : {0, 1}) {
for (int y : {0, 1}) {
if (!i && !y) {
continue; // Root must connect to at least one child.
}
int d = dp2[nc][j][x][y];
if (d < 0) {
continue;
}
// Include current node's value?
if (o || y) {
d += C[i];
}
// Free path ongoing from parent?
setmax(dp[i][j - (o && x ? 1 : 0)][o], d);
}
}
}
}
}
int solve() {
cin >> N >> K;
for (int i = 0; i < N; i++) {
cin >> C[i];
adj[i].clear();
}
for (int i = 0; i < N - 1; i++) {
int a, b;
cin >> a >> b;
a--, b--;
adj[a].push_back(b);
adj[b].push_back(a);
}
// DP
rec(0, -1);
int ans = C[0];
for (int i = 0; i <= K; i++) {
setmax(ans, dp[0][i][0]);
}
return ans;
}
int main() {
int T;
cin >> T;
for (int t = 1; t <= T; t++) {
cout << "Case #" << t << ": " << solve() << endl;
}
return 0;
}
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