[Leetcode] 029. Divide integers (Medium) (C++/python)

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Github:https://github.com/illuz/leetcode

029. Divide, integers (Medium) links：

Title: https://oj.leetcode.com/problems/divide-two-integers/
Code (GitHub): Https://github.com/illuz/leetcode

Test Instructions：

To achieve division, you cannot use multiply, divide, and modulo.

Analysis：

You can't use multiply, divide, and modulo, and the rest, plus, minus, and bitwise operations.

1. Will think of is to reduce again and again, but this will time out.
2. On the basis of 1 optimization, as fast as the power, each time the divisor doubled (with a bitwise operation can be).

There is a hole here, that is, the result may be super int range, so it is best to use a long long to process, and then go Int.

Code：

C++:

Class Solution {public:    int divide (int dividend, int divisor) {ll a = Dividend >= 0? Dividend:-(LL) Dividend;ll b = Divisor >= 0? Divisor:-(LL) Divisor;ll result = 0, c = 0;bool sign = (Dividend > 0 && divisor < 0) | | (Dividend < 0 && divisor > 0); while (a >= b) {c = b;for (int i = 0; a >= C; i++, C <<= 1) {A-= C;result + = (1<<i);}} if (sign) {return Max ((LL) int_min,-result);} else {return MIN ((ll) int_max, result);}}    ;

Python:

Class solution:    # @return An integer    def divide (self, dividend, divisor): sign        = (Dividend < 0 and divisor  > 0) or (Dividend > 0 and Divisor < 0)        A, B = ABS (dividend), ABS (divisor)        ret, c = 0, 0 while        a >= B:            C = b            i = 0 while            a >= C:                A-= c                ret + = (1<<i)                i + = 1                c <<= 1        if Si GN:            ret =-ret        return min (max ( -2147483648, ret), 2147483647)

[Leetcode] 029. Divide integers (Medium) (C++/python)