AlliedModders - [INFO] Bitsums and Operators

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- - [INFO] Bitsums and Operators (https://forums.alliedmods.net/showthread.php?t=90507)

Re: [INFO] Bitsums and Operators

Quote:

Originally Posted by Exolent[jNr] (Post 809946)

Ahem, andrade.
"continue" is never called because the if() statement never returns true.

Code:
array[32] = false bitsum &= ~(1<<32)

Dear Exolent you are right. So the code do not match the profile.

Re: [INFO] Bitsums and Operators

If I have

Code:

(1<<CSW_*)

Is there a way to get the CSW_* ?

Re: [INFO] Bitsums and Operators

If you were doing this in x86 assembly you'd use the bsr (bit search right) instruction.
In pawn I guess your best bet is looping and dividing by two (or shifting right by one) until the number becomes 0, and counting the number of divisions/shifts performed.

Re: [INFO] Bitsums and Operators

Yep, I know only this way : do ++x; while ( ( bitsum /= 2 ) >= 1 )

Re: [INFO] Bitsums and Operators

PHP Code:


		
			
#include <amxmodx>
#include <amxmisc>

#define PLUGIN    "New Plugin"
#define AUTHOR    "Unknown"
#define VERSION    "1.0"

public plugin_init()
{
    register_plugin(PLUGIN, VERSION, AUTHOR)    
    register_clcmd("some","some");    
}

public some(id)
{
    new value[]  = 1 << 20 | 1 << 13 | 1 << 29
    
    for(new i=0;i<4;i++)
    {
        if(value{i})
        {
            for(new j=0;j<8;j++)
            {            
                if(value{i} & (1 << j))
                {
                    client_print(id,print_chat,"Has (1 << %d)",(8*(3 - i)) + j)
                }
            }
        }
    }
}

PHP Code:


		
			
public some(id)
{
    new value[]  = ~(1 << 29)
    
    for(new i=0;i<4;i++)
    {
        if(value{i})
        {
            for(new j=7;j>=0;j--)
            {            
                if(value{i} & (1 << j))
                {
                    client_print(id,print_console,"Has (1 << %d)",(8*(3-i)) + j)
                }
            }
        }
    }
}

PHP Code:


		
			
public some(id)
{
    new value[]  = ~(1 << 3)
    
    new index
    
    for(new i=3;i>=0;i--)
    {
        if(value{i})
        {
            for(new j=0;j<=7;j++,index++)
            {            
                if(value{i} & (1 << j))
                {
                    client_print(id,print_console,"Has (1 << %d)",index)
                }
            }
        }
        else
            index += 8;
    }
}

Re: [INFO] Bitsums and Operators

Quote:

Originally Posted by Emp` (Post 810243)

If I have

Code:

(1<<CSW_*)

Is there a way to get the CSW_* ?

PHP Code:


		
			
#define AddFlag(%1,%2)    ( %1 |= ( 1 << (%2-1) ) )
#define RemoveFlag(%1,%2) ( %1 &= ~( 1 << (%2-1) ) )
#define CheckFlag(%1,%2)  ( %1 & ( 1 << (%2-1) ) )

public Test()
{
    new iWeapList;
    new szWeap[41];

    AddFlag( iWeapList , CSW_AWP );
    AddFlag( iWeapList , CSW_DEAGLE );
    AddFlag( iWeapList , CSW_SCOUT );
    AddFlag( iWeapList , CSW_HEGRENADE );
    
    for ( new i = 1 ; i < 32 ; i++ )
    {
        if ( CheckFlag( iWeapList , i ) )
        {
            get_weaponname( i , szWeap , 40 );
            server_print("Found %s" , szWeap );
        }
    }
}

Re: [INFO] Bitsums and Operators

You should also add the '^' operator to this topic.
It switches the bit.

Code:

new bool:someBool[33];

public switchVar(client)
{
    someBool[client] = !someBool[client];
}

:arrow:

Code:

new someBitsum;

public switchVar(client)
{
    someBitsum ^= (1 << (client - 1));
}

Re: [INFO] Bitsums and Operators

Quote:

Originally Posted by Exolent[jNr] (Post 810450)

You should also add the '^' operator to this topic.
It switches the bit.

Code:
new bool:someBool[33];

public switchVar(client) { someBool[client] = !someBool[client];
}

:arrow:
Code:
new someBitsum;

public switchVar(client) { someBitsum ^= (1 << (client - 1));
}

It can also check if a flag is present in one, and only one, of the compared bitsums. It's not used often, but it may be useful.

Code:

new iFlag1 = (1<<0)

new iFlag2 = (1<<0)



new iResult = iFlag1 ^ iFlag2 // = 0

Re: [INFO] Bitsums and Operators

Stupid trivia. Why does this function:

PHP Code:


		
			
public some(id)
{
    static const indexes[] = {0,0x18,0x10,0x8};
    
    new value[]  = !"@@ "
    
    new index
    
    for(new i=3;i>=0;i--)
    {
        if(value{i})
        {
            for(new j=0;j<=7;j++,index++)
            {            
                if(value{i} & (1 << j))
                {
                    client_print(id,print_console,"Has (1 << %d)",index)
                }
            }
        }
        else
            index = indexes[i];
    }
}

Outputs:

Code:

Has (1 << 13)

Has (1 << 22)

Has (1 << 30)