Write Python code for converting a decimal number to it’s binary equivalent and vice-versa.
Example:
From decimal to binary Input : 8 Output : 1 0 0 0 From binary to decimal Input : 100 Output : 4
Decimal to binary
Keep calling conversion function with n/2 till n > 1, later perform n % 1 to get MSB of converted binary number. Example :- 7 1). 7/2 = Quotient = 3(grater than 1), Remainder = 1. 2). 3/2 = Quotient = 1(not grater than 1), Remainder = 1. 3). 1%2 = Remainder = 1. Therefore, answer is 111.
# Function to print binary number for the # input decimal using recursion def decimalToBinary(n): if (n > 1 ): # divide with integral result # (discard remainder) decimalToBinary(n / / 2 ) print (n % 2 , end = ' ' ) # Driver code if __name__ = = '__main__' : decimalToBinary( 8 ) print ( "\n" ) decimalToBinary( 18 ) print ( "\n" ) decimalToBinary( 7 ) print ( "\n" ) |
Output:
1 0 0 0 1 0 0 1 0 1 1 1
Decimal to binary using bin():
# Function to convert Decimal number # to Binary number def decimalToBinary(n): return bin (n).replace( "0b" ,"") # Driver code if __name__ = = '__main__' : print (decimalToBinary( 8 )) print (decimalToBinary( 18 )) print (decimalToBinary( 7 )) |
Output:
1000 10010 111
Binary to decimal
Example -: 1011 1). Take modulo of given binary number with 10. (1011 % 10 = 1) 2). Multiply rem with 2 raised to the power it's position from right end. (1 * 2^0) Note that we start counting position with 0. 3). Add result with previously generated result. decimal = decimal + (1 * 2^0) 4). Update binary number by dividing it by 10. (1011 / 10 = 101) 5). Keep repeating upper steps till binary > 0. Final Conversion -: (1 * 2^3) + (0 * 2^2) + (1 * 2^1) + (1 * 2^0) = 11
# Function calculates the decimal equivalent # to given binary number def binaryToDecimal(binary): binary1 = binary decimal, i, n = 0 , 0 , 0 while (binary ! = 0 ): dec = binary % 10 decimal = decimal + dec * pow ( 2 , i) binary = binary / / 10 i + = 1 print (decimal) # Driver code if __name__ = = '__main__' : binaryToDecimal( 100 ) binaryToDecimal( 101 ) binaryToDecimal( 1001 ) |
Output:
4 5 9
Binary to decimal using int():
# Function to convert Binary number # to Decimal number def binaryToDecimal(n): return int (n, 2 ) # Driver code if __name__ = = '__main__' : print (binaryToDecimal( '100' )) print (binaryToDecimal( '101' )) print (binaryToDecimal( '1001' )) |
Output:
4 5 9
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