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Given an integer (signed 32 bits), write a function to check whether it is a power of 4. Example 1: Input: 16 Output: true Example 2: Input: 5 Output: 阅读全文
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Given an integer, write a function to determine if it is a power of three. Example 1: Input: 27 Output: true Example 2: Input: 0 Output: false Example 阅读全文
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Given a positive integer num, write a function which returns True if num is a perfect square else False. Note: Do not use any built in library functio 阅读全文
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Find the nth digit of the infinite integer sequence 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, ... Note: n is positive and will fit within the range of a 32 b 阅读全文
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Write a program to check whether a given number is an ugly number. Ugly numbers are positive numbers whose prime factors only include 2, 3, 5. Example 阅读全文