function rob(a, b, target) {
var hash = {}
var stack = [a]
while (queue.length) {
var node = stack.pop()
stack[target - node.val] = 1;
if (node.left) {
stack.push(node.left)
}
if (node.right) {
stack.push(node.right)
}
}
var stack = [b]
while (queue.length) {
var node = stack.pop()
if (stack[node.val] == 1) {
return true
}
if (node.left) {
stack.push(node.left)
}
if (node.right) {
stack.push(node.right)
}
}
return false
}