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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