#include <vector> using namespace std; int query(vector<int> islands); // Declaration of the grader's function int findEgg(int N, vector<pair<int, int>> bridges) { // Build adjacency list vector<vector<int>> adj(N + 1); for (auto& edge : bridges) { adj[edge.first].push_back(edge.second); adj[edge.second].push_back(edge.first); } // Binary search approach on the tree // Start from node 1 and traverse the tree int current = 1; while (true) { // Check each subtree of current node bool found = false; for (int neighbor : adj[current]) { // Get all nodes in this subtree (excluding parent path) vector<int> subtree; vector<bool> visited(N + 1, false); // DFS to collect subtree nodes function<void(int, int)> dfs = [&](int node, int parent) { visited[node] = true; subtree.push_back(node); for (int next : adj[node]) { if (next != parent && !visited[next]) { dfs(next, node); } } }; dfs(neighbor, current); // Query this subtree if (query(subtree) == 1) { current = neighbor; found = true; break; } } // If no subtree contains the egg, it must be at current node if (!found) { return current; } } }

eastereggs.cpp: In function 'int findEgg(int, std::vector<std::pair<int, int> >)':
eastereggs.cpp:28:13: error: 'function' was not declared in this scope
   28 |             function<void(int, int)> dfs = [&](int node, int parent) {
      |             ^~~~~~~~
eastereggs.cpp:2:1: note: 'std::function' is defined in header '<functional>'; did you forget to '#include <functional>'?
    1 | #include <vector>
  +++ |+#include <functional>
    2 | using namespace std;
eastereggs.cpp:28:35: error: expression list treated as compound expression in functional cast [-fpermissive]
   28 |             function<void(int, int)> dfs = [&](int node, int parent) {
      |                                   ^
eastereggs.cpp:28:22: error: expected primary-expression before 'void'
   28 |             function<void(int, int)> dfs = [&](int node, int parent) {
      |                      ^~~~
eastereggs.cpp:38:13: error: 'dfs' was not declared in this scope
   38 |             dfs(neighbor, current);
      |             ^~~