day 4 done

2024/04/part 1 solution.py

@@ -0,0 +1,69 @@
+testing = 0
+if not testing:
+    with open(r'2024/04\input.txt', 'r') as file:
+        input = file.read()
+else:
+    input = '''....XXMAS.
+.SAMXMS...
+...S..A...
+..A.A.MS.X
+XMASAMX.MM
+X.....XA.A
+S.S.S.S.SS
+.A.A.A.A.A
+..M.M.M.MM
+.X.X.XMASX'''
+
+# word search, 
+# allows words to be horizontal, vertical, diagonal, written backwards, or even overlapping other words
+# test input has 18 words
+
+def count_occurance(input, WORD = 'XMAS'):
+    rows = len(input)
+    cols = len(input[0])
+    word_len = len(WORD)
+    directions = {
+            'north': (0, -1),
+            'north_east': (1, -1),
+            'east': (1, 0), 
+            'south_east': (1, 1),
+            'south': (0, 1), 
+            'south_west': (-1, 1),
+            'west': (-1, 0),
+            'north_west': (-1, -1),
+        }
+
+    def am_i_still_in_grid(x,y):
+        'Returns True if the coordinates are within the grid'
+        return 0 <= x < rows and 0 <= y < cols
+    
+
+    def search_from(start_x, start_y, delta_x, delta_y):
+        """
+        Check if the word can be found starting from (start_x, start_y) 
+        in the direction specified by (delta_x, delta_y).
+        """
+        for i in range(word_len):
+            # Calculate the new coordinates
+            new_x = start_x + i * delta_x
+            new_y = start_y + i * delta_y
+            
+            # Check if the new coordinates are within the grid and match the word
+            if not am_i_still_in_grid(new_x, new_y) or input[new_x][new_y] != WORD[i]:
+                return False
+        
+        # If all characters match, return True
+        return True
+
+    word_count = 0
+    for x in range(rows):
+        for y in range(cols):
+            for direction in directions.values():
+                if search_from(x, y, direction[0], direction[1]):
+                    word_count += 1
+
+    return word_count
+
+lines = input.split('\n')
+print(count_occurance(lines))
+