java help plz - ජාවා ‍දන්න කෙනෙක් එනවද

[TakurZ]

java help plz - ජාවා ‍දන්න කෙනෙක් එනවද

int a1 = -5; // -5 = 10000000000000000000000000000101


int b = a1<<1; // 10000000000000000000000000000101 -> 10000000000000000000000000001010
int c = a1>>1;//10000000000000000000000000000101 -> 10000000000000000000000000000010

System.out.println (b);
System.out.println (c);


meka execute kalama b = -10 enawa pehadilii
namuth c = -3 enne eka apahadilii

danna kenek udawwak denawada plz?

 

[TakurZ]

BUMP

thnx nelik, bump ekata

 

[TakurZ]

thnx bumppppp

 

[TakurZ]

bump

අෆ්ෆේ උඹව දැක්ක කල්; දැන්නං උඹෙ කෙසුත් පැහිල මයෙ හිතේ
btw thnx 4 d bump

 

[cspmaxx]

බ අ ම් අප්

 

[Chamal Chamikara]

machan ube uththare waradi uththare -3 neme -2, -5>>1 shift kalama enne 10000000000000000000000000000010 thama oka decimal kalama uththare -2 ne ban (10000000000000000000000000000010)decimal=[-(2x1+0x1)=-2]

 

[TakurZ]

machan ube uththare waradi uththare -3 neme -2, -5>>1 shift kalama enne 10000000000000000000000000000010 thama oka decimal kalama uththare -2 ne ban (10000000000000000000000000000010)decimal=[-(2x1+0x1)=-2]

mcn execute karala balahan -3 uththare enne

 

[TakurZ]

බ අ ම් අප්

ත් ඈ න් ක් ස්
​

 

[Chamal Chamikara]

mcn execute karala balahan -3 uththare enne

wa8

 

[Jolly_Roger]

machan ube uththare waradi uththare -3 neme -2, -5>>1 shift kalama enne 10000000000000000000000000000010 thama oka decimal kalama uththare -2 ne ban (10000000000000000000000000000010)decimal=[-(2x1+0x1)=-2]

eka thama math baluwe.. eth oka execute kalama enne -3

 

[Chamal Chamikara]

class BitWise{

public static void main(String arg[]){
int a=-5;
System.out.println("a>>2"+(a>>2));

}

}



run karala balanna uththare -2 i

 

[TakurZ]

class BitWise{

public static void main(String arg[]){
int a=-5;
System.out.println("a>>2"+(a>>2));

}

}



run karala balanna uththare -2 i

class BitWise2{

public static void main(String arg[]){
int a= -5;

int c = a>>1;

System.out.println (c);

}
}

run karala balanna uththare -3 i

 

[shenoxxx]

අෆ්ෆේ උඹව දැක්ක කල්; දැන්නං උඹෙ කෙසුත් පැහිල මයෙ හිතේ
btw thnx 4 d bump

ලාවට එකක් දෙකක් පැහිලා හේනා ටිකක්වත් වක් කරගන්න ඕනේ
උබ තමා වැඩිය පෙන්ට නැත්තේ.

 

[Chamal Chamikara]

ah sorry ban -5>>1 eka -3 thamai ube uththare waradi mama kalin -5>>2 karala thiyenne -5>>1 kiyanne 10000000000000000000000000000011 e kiyanne -3
eka enne mehemai -5 2's complement eka 11111111111111111111111111111011 oke >>1 11111111111111111111111111111101 meken 1k adu kalama 11111111111111111111111111111100 eke binary 10000000000000000000000000000011 e kiyanne -3 i

 

[TakurZ]

ah sorry ban -5>>1 eka -3 thamai ube uththare waradi mama kalin -5>>2 karala thiyenne -5>>1 kiyanne 10000000000000000000000000000011 e kiyanne -3
eka enne mehemai -5 2's complement eka 11111111111111111111111111111011 oke >>1 11111111111111111111111111111101 meken 1k adu kalama 11111111111111111111111111111100 eke binary 10000000000000000000000000000011 e kiyanne -3 i

//int -5
<<1
//10000000000000000000000000000101 -> true code
//11111111111111111111111111111010 -> inverted code
//11111111111111111111111111110100 <- shifting 1 digit
//+1 to right most digit -> complement code
//11111111111111111111111111110101 -> complement code
//btw true code of this complement code is
//10000000000000000000000000001010 = -10 so answer is ok
------------------------------------------------
//int -5
>>1
//10000000000000000000000000000101 -> true code
//11111111111111111111111111111010 -> inverted code
//11111111111111111111111111111101 -> shifting 1 digit
//+1 to right most digit -> complement code
//11111111111111111111111111111110 -> complement code or machine code
//btw true code of this complement code is
//10000000000000000000000000000001 = -1 so answer isn't ok

poddak explain karanawada mcn mama meke wena widiya weradiyata therum aranda danne ne

 

[TakurZ]

ලාවට එකක් දෙකක් පැහිලා හේනා ටිකක්වත් වක් කරගන්න ඕනේ
උබ තමා වැඩිය පෙන්ට නැත්තේ.

පහුගිය දොහේ ඩිංගක් ඉතර බිසී උනා බං

 

[Chamal Chamikara]

//11111111111111111111111111111101 -> shifting 1 digit meka thiyenne 2's complement wala thiyenne eka decimal karanna issaralama meke 2's complement eka ain karala 1's complenent karanna meken ekak adu karanna ona etapasse enne 11111111111111111111111111111100 ne dan meka thiyenne 1's complement wala dan 1's complement binary karanna 1 thiyena than 0 karala 0 ewa 1 karanna ona dan binary code eka 10000000000000000000000000000011 ne me kiyanne -3 (1x2+1x1=3)

 

[TakurZ]

//11111111111111111111111111111101 -> shifting 1 digit meka thiyenne 2's complement wala thiyenne eka decimal karanna issaralama meke 2's complement eka ain karala 1's complenent karanna meken ekak adu karanna ona etapasse enne 11111111111111111111111111111100 ne dan meka thiyenne 1's complement wala dan 1's complement binary karanna 1 thiyena than 0 karala 0 ewa 1 karanna ona dan binary code eka 10000000000000000000000000000011 ne me kiyanne -3 (1x2+1x1=3)

ස්තූතියි මචං, දැන්නං යන්තං තේරුනා.. යන්තං කිව්වට හොඳටම මචං ඒත් unsigned shift >>> එකේදි -1 සිද්ධිය වලංගු නෑ නේද?

 

[c.palihakkara]

you confused with how to represent minus numbers (singed integers) in JVM

-1 is represent by 11111111111111111111111111111111
1 is represent by 00000000000000000000000000000001

so -5 is represent by 11111111111111111111111111111011

and shift Operations are
>> shift bits right with sign extension
>>= shift bits right with sign extension and assign
<< shift bits left
<<= shift bits left and assign
>>> unsigned bit shift right
>>>= unsigned bit shift right and assign

so simply this is gonna happens
a = -5 11111111111111111111111111111011
b = -10 11111111111111111111111111110110 after shift one bit left
c = -3 11111111111111111111111111111101 after shift one bit right with sign extension


You can run this program to see it

public class test {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int a = -5; // a = -5    11111111111111111111111111111011
        System.out.print ("a = "+a+"    ");
        System.out.println (Integer.toBinaryString(a));
        
        int b = a<<1; // b = -10   11111111111111111111111111111011 -> 11111111111111111111111111110110 
        System.out.print("b = "+b+"   ");
        System.out.print (Integer.toBinaryString(b));
        System.out.println("     after shift one bit left");
        
        int c = a>>1;//c = -3   11111111111111111111111111111011 -> 11111111111111111111111111111101
        
        System.out.print ("c = "+c+"    ");
        System.out.print (Integer.toBinaryString(c));
        System.out.println("     after shift one bit right with sign extension");
        
    }

}

 

[TakurZ]

you confused with how to represent minus numbers (singed integers) in JVM

-1 is represent by 11111111111111111111111111111111
1 is represent by 00000000000000000000000000000001

so -5 is represent by 11111111111111111111111111111011

and shift Operations are
>> shift bits right with sign extension
>>= shift bits right with sign extension and assign
<< shift bits left
<<= shift bits left and assign
>>> unsigned bit shift right
>>>= unsigned bit shift right and assign

so simply this is gonna happens
a = -5 11111111111111111111111111111011
b = -10 11111111111111111111111111110110 after shift one bit left
c = -3 11111111111111111111111111111101 after shift one bit right with sign extension


You can run this program to see it

public class test {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int a = -5; // a = -5    11111111111111111111111111111011
        System.out.print ("a = "+a+"    ");
        System.out.println (Integer.toBinaryString(a));
        
        int b = a<<1; // b = -10   11111111111111111111111111111011 -> 11111111111111111111111111110110 
        System.out.print("b = "+b+"   ");
        System.out.print (Integer.toBinaryString(b));
        System.out.println("     after shift one bit left");
        
        int c = a>>1;//c = -3   11111111111111111111111111111011 -> 11111111111111111111111111111101
        
        System.out.print ("c = "+c+"    ");
        System.out.print (Integer.toBinaryString(c));
        System.out.println("     after shift one bit right with sign extension");
        
    }

}

ya mcn that's true I'm struggling here with minus representations
මචං මම PM එකක් දැම්මා පොඩ්ඩක් බලනවද