Create maximum-difference-score-in-a-grid.py

Author: kamyu104

Python/maximum-difference-score-in-a-grid.py

@@ -0,0 +1,23 @@
+# Time:  O(m * n)
+# Space: O(1)
+
+# dp
+class Solution(object):
+    def maxScore(self, grid):
+        """
+        :type grid: List[List[int]]
+        :rtype: int
+        """
+        POS_INF = float("inf")
+        NEG_INF = float("-inf")
+        result = NEG_INF
+        for i in xrange(len(grid)):
+            for j in xrange(len(grid[0])):
+                mn = POS_INF
+                if i-1 >= 0:
+                    mn = min(mn, grid[i-1][j])
+                if j-1 >= 0:
+                    mn = min(mn, grid[i][j-1])
+                result = max(result, grid[i][j]-mn)
+                grid[i][j] = min(grid[i][j], mn)
+        return result