feat (day 146): implement left-handed seat availability check with orientation-aware neighbor rules

Author: JohnSunny21

FreeCodeCamp/CodingQ/LeftHandedSeat.py

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+"""  
+Left-Handed Seat at the Table
+Given a 4x2 matrix (array of arrays) representing the seating arrangement for a meal, determine how many seats a left-handed person can sit at.
+
+A left-handed person cannot sit where a right-handed person would be in the seat to the immediate left of them.
+In the given matrix:
+
+An "R" is a seat occupied by a right-handed person.
+An "L" is a seat occupied by a left-handed person.
+An "U" is an unoccupied seat.
+Only unoccupied seats are available to sit at.
+The seats in the top row are facing "down", and the seats in the bottom row are facing "up" (like a table), so left and right are relative to the seat's orientation.
+Corner seats only have one seat next to them.
+For example, in the given matrix:
+
+[
+  ["U", "R", "U", "L"],
+  ["U", "R", "R", "R"]
+]
+The top-left seat is cannot be sat in because there's a right-handed person to the left. The other two open seats can be sat in because there isn't a right-handed person to the left.
+"""
+
+import unittest
+
+class LeftHandedSeatTest(unittest.TestCase):
+
+    def test1(self):
+        self.assertEqual(find_left_handed_seats([["U", "R", "U", "L"], ["U", "R", "R", "R"]]), 2)
+    
+    def test2(self):
+        self.assertEqual(find_left_handed_seats([["U", "U", "U", "U"], ["U", "U", "U", "U"]]), 8)
+
+    def test3(self):
+        self.assertEqual(find_left_handed_seats([["U", "R", "U", "R"], ["L", "R", "R", "U"]]), 0)
+    
+    def test4(self):
+        self.assertEqual(find_left_handed_seats([["L", "U", "R", "R"], ["L", "U", "R", "R"]]), 1)
+
+    def test5(self):
+        self.assertEqual(find_left_handed_seats([["U", "R", "U", "U"], ["U", "U", "L", "U"]]), 5)
+
+
+def find_left_handed_seats(table):
+
+    rows, cols = len(table), len(table[0])
+
+    count = 0
+
+    for r in range(rows):
+        for c in range(cols):
+            if table[r][c] != 'U':
+                continue
+                # Determine immediate-left neighbor based on orientation
+            left_c = c + 1 if r == 0 else c - 1
+            if(0 <= left_c < cols):
+                if table[r][left_c] == 'R':
+                    continue
+
+            count += 1
+
+    return count
+
+
+
+if __name__ == "__main__":
+    unittest.main()