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#include <cmath>
#include <iostream>
#include <unordered_map>
using namespace std;
const int LIM = 200000;
int N, M, Q;
unordered_map<int, int> adj[LIM];
// big_ind_flow[u][v] = the total flow from u to v through length-2 paths
// if u is a "big" node with degree > sqrt(M), otherwise big_ind_flow[u] = {}.
unordered_map<int, long long> big_ind_flow[LIM];
inline int degree(int i) {
return adj[i].size();
}
inline bool is_big(int i) {
return degree(i) > (int)sqrt(M);
}
void solve() {
for (int i = 0; i < LIM; i++) {
adj[i].clear();
big_ind_flow[i].clear();
}
cin >> N >> M >> Q;
for (int i = 0, a, b, c; i < M; i++) {
cin >> a >> b >> c;
a--, b--;
adj[a][b] = adj[b][a] = c;
}
// O(M^1.5) - precompute length-2 max flows for "big" nodes (deg > sqrt(M)).
for (int u = 0; u < N; u++) {
if (is_big(u)) {
for (auto const &[mid, c1] : adj[u]) {
for (auto const &[v, c2] : adj[mid]) {
if (u != v) {
big_ind_flow[u][v] += min(c1, c2);
}
}
}
}
}
// Answer queries.
for (int i = 0, x, y; i < Q; i++) {
cin >> x >> y;
x--, y--;
if (degree(x) < degree(y)) {
swap(x, y); // Always process queries from bigger node.
}
long long ans = 0;
if (adj[x].count(y)) {
ans += 2*adj[x][y]; // Fly direct x -> y.
}
if (is_big(x)) {
ans += big_ind_flow[x][y];
} else {
for (auto const &[mid, c1] : adj[x]) { // O(sqrt(M))
if (adj[mid].count(y)) {
ans += min(c1, adj[mid][y]); // Fly indirect x -> mid -> y.
}
}
}
cout << " " << ans;
}
}
int main() {
int T;
cin >> T;
for (int t = 1; t <= T; t++) {
cout << "Case #" << t << ":";
solve();
cout << endl;
}
return 0;
}
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