Completed leetcode 322 and 198

CoinChange.py

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+#Time Complexity: O(n*m) where n is the amount and m is the number of coins
+#Space Complexity: O(n) where n is the amount
+
+class Solution(object):
+    def coinChange(self, coins, amount):
+        """
+        :type coins: List[int]
+        :type amount: int
+        :rtype: int
+        """
+        n = amount
+        dp = [99999] * (n + 1)
+        dp[0] = 0
+
+        for coin in coins:
+            for j in range(coin, n + 1):
+                dp[j] = min(dp[j], 1 + dp[j - coin])
+
+        return -1 if dp[n] == 99999 else dp[n]

HouseRobber.py

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+#Time Complexity: O(n) where n is the length of the input list
+#Space Complexity: O(1) since we are using constant space
+
+class Solution(object):
+    def rob(self, nums):
+        """
+        :type nums: List[int]
+        :rtype: int
+        """
+        """n = len(nums)
+        if n == 1:
+            return nums[0]
+        dp = [0] * n
+        dp[0] = nums[0]
+        dp[1] = max(nums[0], nums[1])
+        for i in range(2, len(nums)):
+            dp[i] = max(dp[i - 1], dp[i - 2] + nums[i])
+
+        return dp[-1]"""
+        n = len(nums)
+        if n == 1:
+            return nums[0]
+        prev = nums[0]
+        curr = max(nums[0], nums[1])
+        for i in range(2, len(nums)):
+            temp = curr
+            curr = max(curr, prev + nums[i])
+            prev = temp
+
+        return curr
+