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

divide-two-integers.java

/**

**/

class Solution {
    public int divide(int dividend, int divisor) {
        if (dividend == Integer.MIN_VALUE && divisor == -1) {
            return Integer.MAX_VALUE;
        }
        if (divisor == 1) {
            return dividend;
        }
        
        int r = Math.abs(dividend); // abs(Integer.MIN_VALUE) -> Integer.MIN_VALUE 
        int l = Math.abs(divisor);
        
        int sign = 0;
        if (dividend > 0 && divisor > 0 || dividend < 0 && divisor < 0) {
            sign = 1;
        } else {
            sign = -1;
        }
        
        int result = 0;
        
        while(r - l >= 0) {
            int i = 1; // bit move
            while(  r - (l << i) >= 0) {
                i ++; 
            }
            result += (1 << (i - 1)); // multiplier
            r -= (l << (i - 1));
        }
        return sign == 1 ? result : -result;
    }
}