I recently had a phone interview with FB and I was asked this question with a slight twist\n\n**Question:**\nhttps://leetcode.com/problems/serialize-and-deserialize-binary-tree/\nThe serialize method is only allowed to return a list of integers and no nulls are allowed. The solution should work for positive and negative numbers.\n\nI hadn\'t solved it before but managed to work through the problem and come up with a solution to solve it. The key was I didn\'t panic when I got a problem that I hadn\'t practiced since I trusted my preparation and worked my way through the problem while thinking out loud and managed to code the solution. \n\nI got the confirmation that I\'ve made it to the onsite interviews.

I recently had a phone interview with FB and I was asked this question with a slight twist\n\nQuestion:\nhttps://leetcode.com/problems/serialize-and-deserialize