zoukankan      html  css  js  c++  java
  • LeetCode Medium: 29. Divide Two Integers

    一、题目

    Given two integers dividend and divisor, divide two integers without using multiplication, division and mod operator.

    Return the quotient after dividing dividend by divisor.

    The integer division should truncate toward zero.

    Example 1:

    Input: dividend = 10, divisor = 3
    Output: 3

    Example 2:

    Input: dividend = 7, divisor = -3
    Output: -2

    Note:

    • Both dividend and divisor will be 32-bit signed integers.
    • The divisor will never be 0.
    • Assume we are dealing with an environment which could only store integers within the 32-bit signed integer range: [−231,  231 − 1]. For the purpose of this problem, assume that your function returns 231 − 1 when the division result overflows.

    题目大意:不用乘除、取模等运算符,做除法运算

    二、思路

    这道题可以使用位移运算,借助减法每次减去除数的倍数,每次对商的更新取一个位移操作。

    三、代码

    #coding:utf-8
    def divide(dividend, divisor):
        """
        :type dividend: int
        :type divisor: int
        :rtype: int
        """
        MAX_INT = 2147483647
        sign = 1 if (dividend > 0 and divisor > 0) or (dividend < 0 and divisor < 0) else -1
        quotient = 0
        dividend = abs(dividend)
        divisor = abs(divisor)
        while dividend >= divisor:
            k = 0
            tmp = divisor
            while dividend >= tmp:
                dividend -= tmp
                quotient += 1 << k     #移位运算符比加减优先级高
                tmp <<= 1
                k += 1
        quotient = sign * quotient
        if quotient > MAX_INT:
            quotient = MAX_INT
        print(quotient)
        return quotient
    
    if __name__ == '__main__':
        divide(21,5)
    

      代码参考:https://blog.csdn.net/qian2729/article/details/50528758

    既然无论如何时间都会过去,为什么不选择做些有意义的事情呢
  • 相关阅读:
    浅谈JavaScript中forEach与each
    Angular.js中使用$watch监听模型变化
    整理:Javascript获取数组中的最大值和最小值的方法汇总
    自定义指令的参数
    ng-disabled 不起作用的解决办法
    理解Angular中的$apply()以及$digest()
    $q -- AngularJS中的服务(理解)
    正则表达式30分钟入门教程(转)
    angular.extend用法实例
    使用angular.bootstrap() 完成模块的手动加载
  • 原文地址:https://www.cnblogs.com/xiaodongsuibi/p/8968637.html
Copyright © 2011-2022 走看看