feat(bit_manipulation): add swap_bits function with doctests and validation

Author: swet40

bit_manipulation/binary_swap_bits.py

@@ -0,0 +1,55 @@
+"""
+Swaps two bits at given positions in an integer using bitwise operators.
+Wikipedia explanation: https://en.wikipedia.org/wiki/Bit_manipulation
+"""
+
+
+def swap_bits(number: int, i: int, j: int) -> int:
+    """
+    Swaps the bits at positions i and j (0-indexed from the right).
+
+    >>> swap_bits(28, 0, 2)  # 11100 → swap rightmost bits 0 and 2
+    25
+    >>> swap_bits(15, 1, 2)  # 1111 → swap bits 1 and 2
+    15
+    >>> swap_bits(10, 0, 3)  # 1010 → swap bits 0 and 3
+    3
+    >>> swap_bits(10.5, 0, 3)
+    Traceback (most recent call last):
+        ...
+    TypeError: All arguments MUST be integers!
+    >>> swap_bits(-5, 1, 3)
+    Traceback (most recent call last):
+        ...
+    ValueError: The number MUST be non-negative!
+    >>> swap_bits(10, -1, 2)
+    Traceback (most recent call last):
+        ...
+    ValueError: Bit positions MUST be non-negative!
+    """
+
+    if not all(isinstance(x, int) for x in (number, i, j)):
+        raise TypeError("All arguments MUST be integers!")
+
+    if number < 0:
+        raise ValueError("The number MUST be non-negative!")
+
+    if i < 0 or j < 0:
+        raise ValueError("Bit positions MUST be non-negative!")
+
+    # Extract the bits at positions i and j
+    bit_i = (number >> i) & 1
+    bit_j = (number >> j) & 1
+
+    # Only swap if the bits are different
+    if bit_i != bit_j:
+        # XOR with a mask that has 1s at i and j
+        number ^= (1 << i) | (1 << j)
+
+    return number
+
+
+if _name_ == "_main_":
+    import doctest
+
+    doctest.testmod()