Not all pieces are as simple as the Rook. The Knight moves in an "L" shape: two squares in one direction, and one in the perpendicular direction. To verify this move, a single comparison is not enough. We must combine multiple conditions using Logical Operators:

• and: All conditions must be true.
• or: At least one condition must be true.
• not: Reverses the result (True becomes False).

The "L" Movement (Math + Logic)

How do we translate the "L" into math? We use the absolute value of the difference between coordinates (the number of steps taken).

Let Delta r = |r1 - r2| and Delta c = |c1 - c2|.

The Knight move is valid if:

(Delta r = 2 AND Delta c = 1) OR (Delta r = 1 AND Delta c = 2)

In Python:

delta_r = abs(r1 - r2)
delta_c = abs(c1 - c2)

knight_move = (delta_r == 2 and delta_c == 1) or (delta_r == 1 and delta_c == 2)2. 

Boundaries

A common mistake for beginners is trying to move a piece off the board (e.g., column "I" or row 9). This causes a critical error in programming called an IndexError. We must always validate that coordinates are within the 0-7 limits.

destination_row = 8 # Imagine incorrect user input

# Validation with AND
# The row must be >= 0 AND it must be <= 7
if destination_row >= 0 and destination_row <= 7:
    print("Move is inside the board")
else:
    print("Error: You fell off the table!")