c++ faster than 95% using unordered_map
\nclass Solution {\npublic:\n    string destCity(vector<vector<string>>& paths) {\n        unordered_map<string, int> map;\n        for (size_t i = 0; i < paths
```\nclass Solution {\npublic:\n    string destCity(vector<vector<string>>& paths) {\n        unordered_map<string, int> map;\n        for (size_t i = 0; i < paths.size(); i++) {\n            map[paths[i][0]] = 1;\n            --map[paths[i][1]];\n        }\n        for (auto iter = map.begin(); iter != map.end(); iter++) {\n            if (iter->second == -1) return iter->first;\n        }\n        return "";\n    }\n};\n```
['C']