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Roman numerals are represented by seven different symbols: I, V, X, L, C, D and M. Symbol ValueI 1V 5X 10L 50C 100D 500M 1000For example, two is writt 阅读全文
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Determine whether an integer is a palindrome. An integer is a palindrome when it reads the same backward as forward. Example 1: Input: 121Output: true 阅读全文
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Given a 32-bit signed integer, reverse digits of an integer. Example 1: Input: 123Output: 321Example 2: Input: -123Output: -321Example 3: Input: 120Ou 阅读全文
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Sherlock Holmes received a note with some strange strings: Let's date! 3485djDkxh4hhGE 2984akDfkkkkggEdsb s&hgsfdk d&Hyscvnm. It took him only a minut 阅读全文
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Given any positive integer N, you are supposed to find all of its prime factors, and write them in the format N = p1k1×p2k2×⋯×pm 阅读全文
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The task of this problem is simple: insert a sequence of distinct positive integers into a hash table, and output the positions of the input numbers. 阅读全文
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Given any permutation of the numbers {0, 1, 2,..., N−1}, it is easy to sort them in increasing order. But what if Swap(0, *) is the ONLY operation tha 阅读全文
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Eva loves to collect coins from all over the universe, including some other planets like Mars. One day she visited a universal shopping mall which cou 阅读全文