initial commit

1 files changed, 80 insertions, 0 deletions

diff --git a/python/11-largest_product_in_a_grid.py b/python/11-largest_product_in_a_grid.py
new file mode 100644
index 0000000..c98a41e
--- /dev/null
+++ b/python/11-largest_product_in_a_grid.py
@@ -0,0 +1,80 @@
+from functools import reduce
+
+grid = [
+    [8, 2, 22, 97, 38, 15, 0, 40, 0, 75, 4, 5, 7, 78, 52, 12, 50, 77, 91, 8],
+    [49, 49, 99, 40, 17, 81, 18, 57, 60, 87, 17, 40, 98, 43, 69, 48, 4, 56, 62, 0],
+    [81, 49, 31, 73, 55, 79, 14, 29, 93, 71, 40, 67, 53, 88, 30, 3, 49, 13, 36, 65],
+    [52, 70, 95, 23, 4, 60, 11, 42, 69, 24, 68, 56, 1, 32, 56, 71, 37, 2, 36, 91],
+    [22, 31, 16, 71, 51, 67, 63, 89, 41, 92, 36, 54, 22, 40, 40, 28, 66, 33, 13, 80],
+    [24, 47, 32, 60, 99, 3, 45, 2, 44, 75, 33, 53, 78, 36, 84, 20, 35, 17, 12, 50],
+    [32, 98, 81, 28, 64, 23, 67, 10, 26, 38, 40, 67, 59, 54, 70, 66, 18, 38, 64, 70],
+    [67, 26, 20, 68, 2, 62, 12, 20, 95, 63, 94, 39, 63, 8, 40, 91, 66, 49, 94, 21],
+    [24, 55, 58, 5, 66, 73, 99, 26, 97, 17, 78, 78, 96, 83, 14, 88, 34, 89, 63, 72],
+    [21, 36, 23, 9, 75, 0, 76, 44, 20, 45, 35, 14, 0, 61, 33, 97, 34, 31, 33, 95],
+    [78, 17, 53, 28, 22, 75, 31, 67, 15, 94, 3, 80, 4, 62, 16, 14, 9, 53, 56, 92],
+    [16, 39, 5, 42, 96, 35, 31, 47, 55, 58, 88, 24, 0, 17, 54, 24, 36, 29, 85, 57],
+    [86, 56, 0, 48, 35, 71, 89, 7, 5, 44, 44, 37, 44, 60, 21, 58, 51, 54, 17, 58],
+    [19, 80, 81, 68, 5, 94, 47, 69, 28, 73, 92, 13, 86, 52, 17, 77, 4, 89, 55, 40],
+    [4, 52, 8, 83, 97, 35, 99, 16, 7, 97, 57, 32, 16, 26, 26, 79, 33, 27, 98, 66],
+    [88, 36, 68, 87, 57, 62, 20, 72, 3, 46, 33, 67, 46, 55, 12, 32, 63, 93, 53, 69],
+    [4, 42, 16, 73, 38, 25, 39, 11, 24, 94, 72, 18, 8, 46, 29, 32, 40, 62, 76, 36],
+    [20, 69, 36, 41, 72, 30, 23, 88, 34, 62, 99, 69, 82, 67, 59, 85, 74, 4, 36, 16],
+    [20, 73, 35, 29, 78, 31, 90, 1, 74, 31, 49, 71, 48, 86, 81, 16, 23, 57, 5, 54],
+    [1, 70, 54, 71, 83, 51, 54, 69, 16, 92, 33, 48, 61, 43, 52, 1, 89, 19, 67, 48]
+]
+
+
+def isCorrectIndex(x, y):
+    if 0 <= x < 20 and 0 <= y < 20:
+        return True
+    return False
+
+
+def getAdjacentNumbers(x, y):
+    adjacent = {
+        'vertical': [],
+        'horizontal': [],
+        'diagonal': [],
+        'anti-diagonal': []
+    }
+
+    for i in range(4):
+        # vertical list
+        modifiedX = x + i
+        if isCorrectIndex(modifiedX, y):
+            adjacent['vertical'].append(grid[modifiedX][y])
+
+        # horizontal list
+        modifiedY = y + i
+        if isCorrectIndex(x, modifiedY):
+            adjacent['horizontal'].append(grid[x][modifiedY])
+
+        # diagonal list
+        if isCorrectIndex(modifiedX, modifiedY):
+            adjacent['diagonal'].append(grid[modifiedX][modifiedY])
+
+    # anti-diagonal list
+    for i, j in zip(range(4), range(4)):
+        AntiDiagModifiedX = x - j
+        modifiedY = y + i
+        if isCorrectIndex(AntiDiagModifiedX, modifiedY):
+            adjacent['anti-diagonal'].append(grid[AntiDiagModifiedX][modifiedY])
+
+    # filtering
+    for key in adjacent.keys():
+        if len(adjacent[key]) != 4:
+            adjacent[key] = []
+
+    return adjacent
+
+
+largest_sum = 0
+positions = ((x, y) for x in range(20) for y in range(20))
+for x, y in positions:
+    adjacent = getAdjacentNumbers(x, y)
+    for key in adjacent.keys():
+        multiplied = reduce(lambda acc, val: acc * val, adjacent[key], 1)
+        if multiplied > largest_sum:
+            largest_sum = multiplied
+
+print(largest_sum)