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Given two strings, find the longest common substring.Return the length of it.NoteThe characters in substring should occur continiously in original str... 阅读全文
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Count the number of k's between 0 and n. k can be 0 - 9.Exampleif n=12, in [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12], we have FIVE 1's (1, 10, 11, 12... 阅读全文
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Compare two strings A and B, determine whether A contains all of the characters in B.The characters in string A and B are all Upper Case letters.Examp... 阅读全文
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For given numbers a and b in function aplusb, return the sum of them.NoteYou don't need to parse the input and output. Just calculate and return.Examp... 阅读全文
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Design an iterator over a binary search tree with the following properties:Elements are visited in ascending order (i.e. an inorder traversal)next() a... 阅读全文
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The code base version is an integer and start from 1 to n. One day, someone commit a bad version in the code case, so it caused itself and the followi... 阅读全文