DOM：
<div class="parent">
<div class="child1">
<div class="child1-1"></div>
<div class="child1-2"></div>
<div class="child1-3"></div>
</div>
<div class="child2">
<div class="child2-1"></div>
<div class="child2-2"></div>
</div>
<div class="child3"></div>
</div>
DFS：
const dfs = (node) => {
if (!node) return [];
const result = [];
const stack = [node];
while (stack.length) {
const item = stack.pop();
result.push(item);
const children = item.children;
if (!children) break;
for (let i = children.length - 1; i >= 0; i--) {
stack.push(children[i])
}
}
return result
}
输出结果
[div.parent, div.child1, div.child1-1, div.child1-2, div.child1-3, div.child2, div.child2-1, div.child2-2, div.child3]
BFS：
const bfs = (node) => {
if (!node) return [];
const result = [];
const queue = [node];
while (queue.length) {
const item = queue.shift()
result.push(item)
const { children } = item
if (!children) break
for (let i = 0; i < children.length; i++) {
queue.push(children[i])
}
}
return result;
}
输出结果
[div.parent, div.child1, div.child2, div.child3, div.child1-1, div.child1-2, div.child1-3, div.child2-1, div.child2-2]
