Add binary_coded_decimal.py

bit_manipulation/bcd_sequence.py

@@ -0,0 +1,33 @@
+def bcd_sequence(num: int) -> str:
+    """
+    Find binary coded decimal(bcd) of integer base 10.
+    Each digit of number is represented by 4 bits binary.
+    Example:
+    >>> bcd_sequence(0)
+    '0b0000'
+    >>> bcd_sequence(3)
+    '0b0011'
+    >>> bcd_sequence(2)
+    '0b0010'
+    >>> bcd_sequence(12)
+    '0b00010010'
+    >>> bcd_sequence(987)
+    '0b100110000111'
+    """
+    bcd = ""
+    while num > 0:
+        digit = num % 10
+        num = int(num / 10)
+        bin_seq = str(bin(digit))[2:]
+        bin_seq = "0" * max(0, 4 - len(bin_seq)) + bin_seq
+        bcd = bin_seq + bcd
+    if bcd == "":
+        bcd = "0" * 4
+    bcd = "0b" + bcd
+    return bcd
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()