Decimal to Binary Conversion - Bitwise Left shift operator

It is a number system conversion from decimal to binary, which is implemented by bitwise left shift operator. The left-shift operator shifts the bits of the decimal value towards left direction. it removes MSB bits and adds bits 0s on LSB of the decimal value.

Decimal to Binary Conversion by Left-shift -Manual calculation

Given decimal value =19, converts into binary bits.

     on each iteration, 
           AND (bitwise operation ) with the decimal value  and 128,  
               if condition is true, returns 1, otherwise 0,     
           the decimal left shift by 1 , 
               resultant value stored on the same decimal value.            
  

n	(decval AND 128) Operation	Decval = decval << by 1
0	bit[0] = (19 AND 128) ? 1:0	38 = 19 <<1
1	bit[1] = (38 AND 128) ? 1:0	76 = 38 <<1
2	bit[2] = (78 AND 128) ? 1:0	152 = 38 <<1
3	bit[3] = (152 AND 128) ? 1:0	304 = 152 <<1
4	bit[4] = (304 AND 128) ? 1:0	608 = 304 <<1
5	bit[5] = (608 AND 128) ? 1:0	1216 = 608 <<1
6	bit[6] = (1216 AND 128) ? 1:0	2432 = 1216 <<1
7	bit[7] = (2432 AND 128) ? 1:0	4864 = 2432 <<1

results of the decimal=19 into binary bits is 00010011.

Decimal to binary conversion by Left-shift Operator - Pseudocode

Declaration
Input	Read integer decval
Output	char bits[9]
Temp var	integer n=0,char abit
Loop	n less-than 8
	bits[n] = decval AND 128 then '1' else '0'
	decval left shift by 1
	n=n+1
End Loop
Output	print,bits

Decimal to Binary Left-shift - C programming code

The c programming code converts a decimal value into binary bits using left-shift operator. The decimal value (integer) is read from user while the program running and returns its binary 8 bits as result.

 

#include <stdio.h>
#include <string.h>

int main() {


   unsigned int decval;
   char bits[9]; int n=0;   
   printf ("\n Bitwise Left-shift Operator Binary Conversion");
   
   printf("\n Enter a Decimal value :" );
   scanf("%u", &decval);
   
   while ( n < 8) {   
                        
     bits[n]= (decval & 128) ? '1' :'0';        
     decval = decval <<1;       
     n++;    
   }
   bits[n] ='\0';
      
   printf("Binary bits :%s",bits);
   return 0;
}

 

Output

  Bitwise Left-shift Operator Binary Conversion

     Enter a Decimal value : 10

     Binary bits : 1010

Related post

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• Binary to decimal using arithmetic operator
• Decimal to 8 bit binary using arithmetic operator
• Decimal to binary using bitwise right-shift operator
• Binary to Decimal using bitwise right-shift operator
• Binary to Decimal using bitwise left-shift operator
• Octal to Binary number system conversion
• Binary to Octal number system conversion
• Hexadecimal to Binary number system conversion
• Binary to Hexadecimal number system conversion

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• decimal to binary using left-shift operator