Adding DP-1 (coin-change)

W2_6_322_coin_change_tabulation.py

@@ -0,0 +1,28 @@
+#Time O(m *n)
+#Space: O(m * n)
+
+class Solution:
+    def coinChange(self, coins: List[int], amount: int) -> int:
+        m_rows= len(coins)
+        n_columns = amount 
+
+        # Creates a matrix of m rows and n columns with 0s
+        dp = [[0] * (n_columns+1) for _ in range(m_rows + 1)]
+
+        for j in range(1, n_columns +1):
+            dp[0][j] = 999999
+
+        for i in range(1, m_rows + 1):
+            for j in range(0, n_columns + 1):
+                # Until amount is less than denominotaor, we consider 0 case only.
+                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]])
+
+        result = dp[m_rows][n_columns]
+
+        if result >= 99999:
+            return -1
+        else:
+            return result