refactor: enhance input validation in n_input_nand_gate function to check for empty list and values that are not 0 and 1

Author: TTAAAN

boolean_algebra/nand_gate.py

@@ -32,7 +32,10 @@ def nand_gate(input_1: int, input_2: int) -> int:
 
 def n_input_nand_gate(inputs: list[int]) -> int:
     """
-    Calculate NAND of a list of input values
+    Generalization of nand_gate() to support n inputs.
+    Calculate NAND of a list of input values.
+    Returns 0 only when all inputs are 1, 1 otherwise.
+
     >>> n_input_nand_gate([1, 0, 1, 1, 0])
     1
     >>> n_input_nand_gate([1, 1, 1, 1, 1])
@@ -45,14 +48,28 @@ def n_input_nand_gate(inputs: list[int]) -> int:
     >>> n_input_nand_gate([1, 1])
     0
 
+    >>> n_input_nand_gate([])
+    Traceback (most recent call last):
+        ...
+    ValueError: Input list cannot be empty
+
     >>> n_input_nand_gate([1])
     Traceback (most recent call last):
         ...
     ValueError: Input list must contain at least two elements
+
+    >>> n_input_nand_gate([2, 1])
+    Traceback (most recent call last):
+        ...
+    ValueError: All inputs must be 0 or 1
     """
 
+    if len(inputs) == 0:
+        raise ValueError("Input list cannot be empty")
     if len(inputs) < 2:
         raise ValueError("Input list must contain at least two elements")
+    if not all(i in (0, 1) for i in inputs):
+        raise ValueError("All inputs must be 0 or 1")
 
     return int(not all(inputs))