algorithm/Week_03/id_1/LeetCode_429_1.java at master · feixiangcode/algorithm · GitHub

43 lines (33 loc) · 1 KB

class Solution {

private List<List<Integer>> result = new ArrayList<>();

public List<List<Integer>> levelOrder(Node root) {

if (root == null) {

return result;

}

List<Integer> nodeVals = new ArrayList<>();

nodeVals.add(root.val);

result.add(nodeVals);

this.bfs(root.children);

return this.result;

}

public void bfs(List<Node> nodes) {

int length = nodes.size();

if (length == 0) {

return;

}

List<Node> childrens = new ArrayList<>();

List<Integer> nodeVals = new ArrayList<>();

for (int i = 0; i < length; i ++) {

Node node = nodes.get(i);

nodeVals.add(node.val);

if (node.children != null) {

Iterator<Node> iterator = node.children.iterator();

while (iterator.hasNext()) {

childrens.add(iterator.next());

}

this.result.add(nodeVals);

this.bfs(childrens);

}

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