29 Divide Two Integers

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

If it is overflow, return MAX_INT.

class Solution {
    public int divide(int dividend, int divisor) {
        long result = divideLong(dividend, divisor);
        return result > Integer.MAX_VALUE ? Integer.MAX_VALUE : (int)result;
    }

    // It's easy to handle edge cases when
    // operate with long numbers rather than int
    public long divideLong(long dividend, long divisor) {

        // Remember the sign
        boolean negative = dividend < 0 != divisor < 0;

        // Make dividend and divisor unsign
        if (dividend < 0) dividend = -dividend;
        if (divisor < 0) divisor = -divisor;

        // Return if nothing to divide
        if (dividend < divisor) return 0;

        // Sum divisor 2, 4, 8, 16, 32 .... times
        long sum = divisor;
        long divide = 1;
        while ((sum+sum) <= dividend) {
            sum += sum;
            divide += divide;
        }

        // Make a recursive call for (devided-sum) and add it to the result
        return negative ? -(divide + divideLong((dividend-sum), divisor)) :
            (divide + divideLong((dividend-sum), divisor));
    }
}

No use of Long

class Solution {
  public int divide(int dividend, int divisor) {
        if (dividend == Integer.MIN_VALUE && divisor == -1) {
            return Integer.MAX_VALUE;
        }

        if (dividend > 0 && divisor > 0) {
            return divideHelper(-dividend, -divisor);
        } else if (dividend > 0) {
            return -divideHelper(-dividend, divisor);
        }
        else if(divisor > 0) {
            return -divideHelper(dividend, -divisor);
        }
        else {
            return divideHelper(dividend, divisor);
        }
    }


    private int divideHelper(int dividend, int divisor) {
        int result = 0;
        int currentDivisor = divisor;
        while(true) {
            if(dividend > divisor) {
                break;
            }
            int temp = 1;
            while(dividend <= currentDivisor << 1 && currentDivisor << 1 < 0) {
                temp = temp << 1;
                currentDivisor = currentDivisor << 1;
            }
            dividend -= currentDivisor;
            result += temp;
            currentDivisor = divisor;
        }
        return result;
    }
}