# Not enough test case

• I think No.261 Graph Valid Tree does not have enough test case. I submitted this code:

``````    if(edges.length == 0 || edges[0].length == 0)   return n == 1;
HashMap<Integer, Boolean> visited = new HashMap<Integer, Boolean>();
List<List<Integer>> unvisited = new ArrayList<List<Integer>>();
for(int i = 0; i < edges.length; i++) {
int[] edge = edges[i];
boolean contains0 = visited.containsKey(edge[0]);
boolean contains1 = visited.containsKey(edge[1]);
if(contains0 && contains1) {
if(!visited.get(edge[0]) && !visited.get(edge[1])){
visited.put(edge[0], true);
visited.put(edge[1], true);
}
else    return false;
}
else if(!contains0 && !contains1) {
visited.put(edge[0], false);
visited.put(edge[1], false);
List<Integer> unv = new ArrayList<Integer>();
}
else {
visited.put(edge[0], true);
visited.put(edge[1], true);
}
}
if(visited.keySet().size() != n)    return false;
if(n == 2)  return true;
for(int i = 0; i < unvisited.size(); i++) {
List<Integer> unv = unvisited.get(i);
if(!visited.get(unv.get(0)) && !visited.get(unv.get(1)))   return false;
}
return true;
``````

For case {{0,1},{0,2},{2,5},{3,4}, {3,5}}, this would output false, however, it is still a valid tree.

• This post is deleted!

• My fault.What I mean is if I use {{0,1},{0,2},{2,5},{3,4}, {3,5}} as the input, my program will output "false", however the input is a valid tree. But my code can still pass all the test cases.

• Thanks @derekyyy! You are correct, I have just published your test case. Thanks for making LeetCode OJ better. :)

Looks like your connection to LeetCode Discuss was lost, please wait while we try to reconnect.