Java Integer Divide divideUnsigned(int dividend, int divisor)

Description

Returns the unsigned quotient of dividing the first argument by the second where each argument and the result is interpreted as an unsigned value.

License

Apache License

Parameter

Parameter	Description
dividend	the value to be divided
divisor	the value doing the dividing

Return

the unsigned quotient of the first argument divided by the second argument

Declaration

public static int divideUnsigned(int dividend, int divisor)

Method Source Code

//package com.java2s;
/*/*from   ww w .  j  av  a 2s  .c  om*/
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

public class Main {
    /**
     * Returns the unsigned quotient of dividing the first argument by
     * the second where each argument and the result is interpreted as
     * an unsigned value.
     * <p>Note that in two's complement arithmetic, the three other
     * basic arithmetic operations of add, subtract, and multiply are
     * bit-wise identical if the two operands are regarded as both
     * being signed or both being unsigned. Therefore separate {@code
     * addUnsigned}, etc. methods are not provided.</p>
     * <p>This method does not use the {@code long} datatype.</p>
     *
     * @param dividend the value to be divided
     * @param divisor the value doing the dividing
     * @return the unsigned quotient of the first argument divided by
     * the second argument
     */
    public static int divideUnsigned(int dividend, int divisor) {
        if (divisor >= 0) {
            if (dividend >= 0) {
                return dividend / divisor;
            }
            // The implementation is a Java port of algorithm described in the book
            // "Hacker's Delight" (section "Unsigned short division from signed division").
            int q = ((dividend >>> 1) / divisor) << 1;
            dividend -= q * divisor;
            if (dividend < 0L || dividend >= divisor) {
                q++;
            }
            return q;
        }
        return dividend >= 0 || dividend < divisor ? 0 : 1;
    }

    /**
     * Returns the unsigned quotient of dividing the first argument by
     * the second where each argument and the result is interpreted as
     * an unsigned value.
     * <p>Note that in two's complement arithmetic, the three other
     * basic arithmetic operations of add, subtract, and multiply are
     * bit-wise identical if the two operands are regarded as both
     * being signed or both being unsigned. Therefore separate {@code
     * addUnsigned}, etc. methods are not provided.</p>
     * <p>This method does not use the {@code BigInteger} datatype.</p>
     *
     * @param dividend the value to be divided
     * @param divisor the value doing the dividing
     * @return the unsigned quotient of the first argument divided by
     * the second argument.
     */
    public static long divideUnsigned(long dividend, long divisor) {
        if (divisor >= 0L) {
            if (dividend >= 0L) {
                return dividend / divisor;
            }
            // The implementation is a Java port of algorithm described in the book
            // "Hacker's Delight" (section "Unsigned short division from signed division").
            long q = ((dividend >>> 1) / divisor) << 1;
            dividend -= q * divisor;
            if (dividend < 0L || dividend >= divisor) {
                q++;
            }
            return q;
        }
        return dividend >= 0L || dividend < divisor ? 0L : 1L;
    }
}