LeetCode (Divide Two Integers)

最新推荐文章于 2021-05-07 19:18:17 发布

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本文介绍了一种不使用乘法、除法和取余操作实现整数除法的算法。通过位移和累加实现了高效的除法运算，并考虑了溢出情况。

Problem:

Divide two integers without using multiplication, division and mod operator.

If it is overflow, return MAX_INT.

Solution:

class Solution {
public:
    int divide(int dividend, int divisor) {
        if ((dividend == INT_MIN && divisor == -1) || divisor == 0) 
            return INT_MAX;;
        long long dvd = labs(dividend), dvs = labs(divisor);
        int res = 0;
        while (dvd >= dvs) { 
            long long temp = dvs, multiple = 1;
            while (dvd >= (temp << 1)) {
                temp <<= 1;
                multiple <<= 1;
            }
            dvd -= temp;
            res += multiple;
        }
        if (dividend >> 31 != divisor >> 31)
            res = -res;
        return res;
    }
};