29. Divide Two Integers(C++)

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) {
        int count=0;
        if (!divisor || (dividend == INT_MIN && divisor == -1))
            return INT_MAX;
        int sign = ((dividend < 0) ^ (divisor < 0)) ? -1 : 1;
        long long dvd = labs(dividend);
        long long dvs = labs(divisor);
        while(dvd>=dvs){
            long long tmp=dvs,mult=1;
            while(dvd>=(tmp<<1)){
                tmp=tmp<<1;
                mult=mult<<1;
            }
            dvd-=tmp;
            count+=mult;
        }
        return sign==1?count:-count;
    }
};