JAVA EASY TO UNDERSTAND (6 LINES) EXPLANATION 100% 1ms
The idea is to store source in hashSet and then make another loop to search on destination in this hashSet\n*  The first and only destination that will not be i
*   The idea is to store source in hashSet and then make another loop to search on destination in this hashSet\n*  The first and only destination that will not be in this hashset will be the answer because it\'s never been the source\n\t\n```\n    public String destCity(List<List<String>> paths) {\n        \n        HashSet<String> myHashSet=new HashSet();\n        for(int i=0;i<paths.size();i++)\n              myHashSet.add(paths.get(i).get(0));\n        \n        for(int i=0;i<paths.size();i++) {\n            if(!myHashSet.contains(paths.get(i).get(1)))\n                return paths.get(i).get(1);\n        }\n        return null; // it says "It is guaranteed that there will be exactly one destination city."\n    }\n```\nVote up if you got the idea!
['Java']