Create allocate-mailboxes.py

Author: kamyu104

Python/allocate-mailboxes.py

@@ -0,0 +1,23 @@
+# Time:  O(m * n^2)
+# Space: O(n)
+
+class Solution(object):
+    def minDistance(self, houses, k):
+        """
+        :type houses: List[int]
+        :type k: int
+        :rtype: int
+        """
+        def cost(prefix, i, j):
+            return (prefix[j+1]-prefix[(i+j+1)//2])-(prefix[(i+j)//2+1]-prefix[i])
+
+        houses.sort()
+        prefix = [0]*(len(houses)+1)
+        for i, h in enumerate(houses):
+            prefix[i+1] = prefix[i]+h
+        dp = [cost(prefix, 0, j) for j in xrange(len(houses))]
+        for m in xrange(1, k):
+            for j in reversed(xrange(m, len(houses))):
+                for i in xrange(m, j+1):
+                    dp[j] = min(dp[j], dp[i-1]+cost(prefix, i, j))
+        return dp[-1]