Design Compressed String Iterator

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(This question has been seen in the interviews of the following companies: , Google)

Design and implement a data structure for a compressed string iterator. It should support the following operations: next and hasNext.

The given compressed string will be in the form of each letter followed by a positive integer representing the number of this letter existing in the original uncompressed string.

next() - if the original string still has uncompressed characters, return the next letter; Otherwise return a white space. hasNext() - Judge whether there is any letter needs to be uncompressed.

Note: Please remember to RESET your class variables declared in StringIterator, as static/class variables are persisted across multiple test cases. Please see here for more details.

Additionally, most of the structure of the original tree should remain. Formally, for any child C with parent P in the original tree, if they are both in the same subtree after the split, then node C should still have the parent P.

You should output the root TreeNode of both subtrees after splitting, in any order.

Example 1:

StringIterator iterator = new StringIterator("L1e2t1C1o1d1e1");; // return 'L'; // return 'e'; // return 'e'; // return 't'; // return 'C'; // return 'o'; // return 'd'
iterator.hasNext(); // return true; // return 'e'
iterator.hasNext(); // return false; // return ' '

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