2 Problems completed

Coin Change.py

@@ -0,0 +1,20 @@
+class Solution:
+    def coinChange(self, coins: List[int], amount: int) -> int:
+        if coins == None or len(coins) ==0:
+            return 0
+        n= len(coins)
+
+        dp=[[0]*(amount+1) for _ in range (n+1)]
+
+        for i in range (1, amount+1):
+            dp[0][i]=amount+1
+
+        for i in range (1, n+1):
+            for j in range (1, amount+1):
+                if j< coins[i-1]:
+                    dp[i][j]= dp[i-1][j]
+                else:
+                    dp[i][j]= min( dp[i-1][j], 1+dp[i][j-coins[i-1]])
+            if dp[n][amount]> amount:
+                return -1
+        return dp[n][amount]

House Robber.py

@@ -0,0 +1,16 @@
+# Time complexity =o(n) and Space Complexity = o(n)
+class Solution:
+    def rob(self, nums: List[int]) -> int:
+        if nums ==0 or len(nums)==0:
+            return 
+        n= len(nums)
+        dp =[[0] * (2 )for j in range (n)]
+        dp[0][0]=0
+        dp[0][1]=nums[0]
+
+        for i in range(1, n):
+            dp[i][0]=max(dp[i-1][0], dp[i-1][1])
+            dp[i][1]=nums[i]+dp[i-1][0]
+
+        return max(dp[n-1][0], dp[n-1][1])
+