vector<int> findMinHeightTrees(int n, vector<vector<int>>& edges) {

vector<vector<int>> graph(n, vector<int>{});

vector<int> res;

for (int i = 0; i < edges.size(); ++i) {

graph[edges[i][0]].push_back(edges[i][1]);

graph[edges[i][1]].push_back(edges[i][0]);

}

for (auto edge : graph) {

for (auto e : edge) {

cout << e << " ";

}

cout << endl;

}

//遍历每个点，计算其高度

vector<vector<int>> points(n, vector<int>{});

for (int i = 0; i < n; ++i) {

//vector<int> visited(n, 0);

int height = bfs(graph, i, n);

cout << height << endl;

points[height - 1].push_back(i);

}

for (auto p : points) {

if (p.size() != 0) {

for (auto i : p) {

res.push_back(i);

}

break;

}

}

return res;

}

int bfs(vector<vector<int>>& graph, int start, int n) {

int maxlen = 0;

queue<int> que;

vector<int> visited(n, 0);

visited[start] = 1;

que.push(start);

while(!que.empty()) {

int size = que.size();

maxlen++;

while (size > 0) {

int node = que.front();

cout << node << "---" ;

que.pop();

for (int i = 0; i < graph[node].size(); ++i) {

if (!visited[graph[node][i]]) {

que.push(graph[node][i]);

visited[graph[node][i]] = 1;

}

}

size--;

}

}

return maxlen;

}

vector<vector<int>> example = { { 1, 0 }, { 1, 2 }, { 1, 3 } };

int n = 4;

Solution sol;

vector<int> res = sol.findMinHeightTrees(n, example);

for (auto r : res) {

cout << r << ", ";

}

cout << endl;

return 0;