https://oj.leetcode.com/problems/divide-two-integers/

Divide Two Integers.java

public class Solution {
    public int divide(int dividend, int divisor) {
        long a = dividend;
        long b = divisor;
        if (a == 0) return 0;
        boolean flag = (a > 0) ^ (b > 0);
        if (a < 0) a = -a;
        if (b < 0) b = -b;
        if (a < b) return 0;
        long ret = 0;
        long count = 1;
        long k = b;
        while (k < a){
            k = k << 1;
            count = count << 1;
        }
        while (count >= 1){
            if (a >= k){
                a -= k;
                ret += count;
                if (a == 0) break;
            }
            k = k >> 1;
            count = count >> 1;
        }
        if (!flag) {
            return (int)(ret);
        }else{
            return -(int)(ret);
        }
    }
}