[مخالف - طلب حل : ]الى كل أصحاب الخبرة في الجافا اتمنى الدخول

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بدأه عطر البنفسج في 23 مارس 2011 · 3 رد · 384 مشاهدة · في JavaSE

مشاركة: واتساب X فيسبوك تيليجرام

#123 مارس 2011 في 10:49 صاحب الموضوع

السلام عليكم انا طالبة مبتائة في الجافا اتمنى تشوفوا شو الخطا في حل

هالاسئلة

1 Problem Specification

Find a suitable algorithm to calculate the parity bit for a given sequence of bits (0's and 1's). We have

two types of parity: even parity and odd parity as explained below.

1.1 Even Parity

Given a sequence of bits you get even parity by adding an additional bit number 1 or 0 such that the

total number of 1's is even as follows.

1001001 -> parity bit = 1

0010100 -> parity bit = 0

1.2 Odd Parity

Given a sequence of bits you get odd parity by adding an additional bit number 1 or 0 such that the

total number of 1's is odd as follows.

1001001 -> parity bit = 0

0010100 -> parity bit = 1

هذا الحل

import java.io.UnsupportedEncodingException;

import static java.lang.System.out;

public final class TestParity

{

// -------------------------- STATIC METHODS --------------------------

private static boolean isOddParity( final byte b )

{

int bb = b;

int bitCount = 0;

for ( int i = 0; i < 8; i++, bb >>>= 1 )

{

if ( ( bb & 1 ) != 0 )

{

bitCount++;

}

return ( bitCount & 1 ) != 0;

}

private static boolean isOddParityViaSosman( final byte b )

{

final int bb = b & 0xff;

int parity = bb ^ ( bb >> 4 );

parity ^= parity >> 2;

parity ^= parity >> 1;

return ( parity & 1 ) != 0;

}

public static void main( String[] args ) throws UnsupportedEncodingException

{

out.println( isOddParity( ( byte ) 0xff ) ); // false

out.println( isOddParity( ( byte ) 0x70 ) ); // true

out.println( isOddParityViaSosman( ( byte ) 0xff ) ); // false

out.println( isOddParityViaSosman( ( byte ) 0x70 ) ); // true

}

#223 مارس 2011 في 13:07

أنا اللي شايفه أن الجواب لا يناسب السؤال

#323 مارس 2011 في 15:15

تفضلي

import java.lang.*;
import javax.swing.*;
public class ParityBit
{
    private static void CalculateParityBit( String s, String parity)
    {
        if(!parity.toLowerCase().equals("odd") && !parity.toLowerCase().equals("even"))
        {
            JOptionPane.showMessageDialog(null, "You can only choose either Even Parity or Odd Parity!");
            return;
        }
        if(s.trim().length() == 0)
        {
            JOptionPane.showMessageDialog(null, "You didn't enter anything!");
            return;
        }
        char[] cArray = s.trim().toCharArray();
        for(char c : cArray)
        {
            if(!Character.isDigit(c) && c != '1' && c != '0')
            {
                JOptionPane.showMessageDialog(null, "You can only enter 1 or 0");
                return;
            }
        }
        if(cArray.length != 7)
        {
            JOptionPane.showMessageDialog(null, "You must enter only 7-bit binary number!");
            return;
        }
        int bitCount = 0;
        for(int i = 0; i < 7; i++)
        {
            if(!Character.isDigit(cArray) || cArray != '1' || cArray != '0')
            {
                if(cArray == '1') bitCount++;
            }
        }
        int parity_bit = parity.toLowerCase().equals("odd") ? (bitCount + 1) % 2 : bitCount % 2;
        JOptionPane.showMessageDialog(null, parity.toUpperCase() + " PARITY: the parity bit is " + parity_bit);
    }

    public static void main( String[] args )
    {
        String myString = JOptionPane.showInputDialog(null,"Enter a 7-bit binary number:");
        if(myString == null) // Cancel button is pressed!
        {
            JOptionPane.showMessageDialog(null, "Good Bye!");
            return;
        }
        String parity = JOptionPane.showInputDialog(null,"Even Parity or Odd Parity? (Type either 'Even' or 'Odd'):");
        if(parity == null)  // Cancel button is pressed!
        {
            JOptionPane.showMessageDialog(null, "Good Bye!");
            return;
        }
        CalculateParityBit(myString, parity);
    }
}