Hard · Trees
Serialize and deserialize
Given the root of a binary tree, encode the tree as a string and decode that string back into a tree. Return both the string and the rebuilt tree, which must have exactly the same shape and values as the original. The reference writes the tree in level order, with # for every missing child and commas between tokens; an empty tree becomes the empty string.
Examples
Example 1
[1,2,3,null,null,4,5]Output: "1,2,3,#,#,4,5,#,#,#,#"
Example 2
[1,2,3]Output: "1,2,3,#,#,#,#"
Rebuild it in the studio
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