05 August 2008
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/*
// Definition for a Node.
class Node {
public int val;
public List<Node> children;
public Node() {}
public Node(int _val) {
val = _val;
}
public Node(int _val, List<Node> _children) {
val = _val;
children = _children;
}
};
*/
class Solution {
public List<List<Integer>> levelOrder(Node root) {
List<List<Integer>> ret = new LinkedList<>();
if (root == null) return ret;
Queue<Node> queue = new LinkedList<>();
queue.offer(root);
while (!queue.isEmpty()) {
List<Integer> curLevel = new LinkedList<>();
int len = queue.size();
for (int i = 0; i < len; i++) {
Node curr = queue.poll();
curLevel.add(curr.val);
for (Node c : curr.children)
queue.offer(c);
}
ret.add(curLevel);
}
return ret;
}
}