diff options
Diffstat (limited to 'other/closest_node_2_nodes.cpp')
-rw-r--r-- | other/closest_node_2_nodes.cpp | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/other/closest_node_2_nodes.cpp b/other/closest_node_2_nodes.cpp new file mode 100644 index 0000000..7b85f22 --- /dev/null +++ b/other/closest_node_2_nodes.cpp @@ -0,0 +1,55 @@ +#include "leetcode.h" + +class Solution { +public: + int closestMeetingNode(vector<int> &edges, int node1, int node2) { + pair<int, int> p1 = dfs(edges, node1, node2); + pair<int, int> p2 = dfs(edges, node2, node1); + if (p1.second != -1 && p1.first < p2.first) + return p1.second; + else if (p2.second != -1 && p2.first < p1.first) + return p2.second; + else if (p1.first == p2.first) { + if (p1.second < p2.second) + return p1.second; + else + return p2.second; + } + return -1; + } + +private: + pair<int, int> dfs(vector<int> &edges, int node1, int node2) { + unordered_map<int, int> um; + int n = edges.size(); + vector<int> vis1(n + 2, 0), vis2(n + 2, 0); + um[node1] = 1; + int len = 0; + while (edges[node1] != -1 && vis1[node1] != 1) { + vis1[node1] = 1; + node1 = edges[node1]; + um[node1] = len++; + } + pair<int, int> pp = make_pair(INT_MAX, -1); + if (um.find(node2) != um.end()) { + pp = make_pair(um[node2], node2); + return pp; + } + while (edges[node2] != -1 && vis2[node2] != 1) { + vis2[node2] = 1; + node2 = edges[node2]; + if (um.find(node2) != um.end()) { + pp = make_pair(um[node2], node2); + return pp; + } + } + return pp; + } +}; + +int main() { + Solution obj; + vector<int> edges1 = {2, 2, 3, -1}, edges2 = {1, 2, -1}; + cout << obj.closestMeetingNode(edges1, 0, 2) << endl; // expect: 2 + cout << obj.closestMeetingNode(edges2, 0, 2) << endl; // expect: 2 +} |