DivideTwoIntegers.java

package bit_manipulation;

/**
 * Created by gouthamvidyapradhan on 13/02/2018. Divide two integers without using multiplication,
 * division and mod operator.
 *
 * <p>If it is overflow, return MAX_INT.
 */
public class DivideTwoIntegers {

  /**
   * Main method
   *
   * @param args
   * @throws Exception
   */
  public static void main(String[] args) throws Exception {
    System.out.println(new DivideTwoIntegers().divide(0, 775));
  }

  public int divide(int dividend, int divisor) {
    if (divisor == 0) return Integer.MAX_VALUE;
    else if (dividend == Integer.MIN_VALUE && divisor == -1) return Integer.MAX_VALUE;
    else if (divisor == 1) return dividend;
    boolean isNegative = ((dividend < 0 && divisor > 0) || (dividend > 0 && divisor < 0));
    dividend = (dividend < 0) ? -dividend : dividend;
    divisor = (divisor < 0) ? -divisor : divisor;
    int sum, result = 0;
    while (true) {
      int d1 = divisor;
      sum = 0;
      if (dividend - d1 == 0) {
        sum += 1;
        result += sum;
        break;
      }
      if (dividend - d1 < 0) break;
      while (dividend - (d1 << 1) > 0) {
        d1 <<= 1;
        sum += 1;
      }
      result += (1 << sum);
      dividend = dividend - d1;
    }
    return isNegative ? -result : result;
  }
}