Merge pull request ashutosh97#163 from pruthvigh/master

Add Buy and sell stock atmost k times for a maximum profit

Author: ashutosh97

Buy-and-Sell-Stock-for-Maximum-Profit/buyAndSellStock.py

@@ -0,0 +1,40 @@
+'''
+Ref: https://www.geeksforgeeks.org/maximum-profit-by-buying-and-selling-a-share-at-most-k-times/
+
+'''
+# Python program to maximize the profit 
+# by doing at most k transactions 
+# given stock prices for n days 
+  
+# Function to find out maximum profit by 
+# buying & selling a share atmost k times  
+# given stock price of n days 
+def maxProfit(prices, n, k): 
+      
+    # Bottom-up DP approach 
+    profit = [[0 for i in range(k + 1)] 
+                 for j in range(n)] 
+      
+    # Profit is zero for the first 
+    # day and for zero transactions 
+    for i in range(1, n): 
+          
+        for j in range(1, k + 1): 
+            max_so_far = 0
+              
+            for l in range(i): 
+                max_so_far = max(max_so_far, prices[i] -
+                            prices[l] + profit[l][j - 1]) 
+                              
+            profit[i][j] = max(profit[i - 1][j], max_so_far) 
+      
+    return profit[n - 1][k] 
+  
+# Driver code 
+k = 2
+prices = [10, 22, 5, 75, 65, 80] 
+n = len(prices) 
+  
+print("Maximum profit is:", 
+       maxProfit(prices, n, k)) 
+  

Buy-and-Sell-Stock-for-Maximum-Profit/problem-statement.txt

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+Ref: https://www.geeksforgeeks.org/maximum-profit-by-buying-and-selling-a-share-at-most-k-times/
+
+
+In share trading, a buyer buys shares and sells on a future date. Given the stock price of n days, the trader is allowed to make at most k transactions, where a new transaction can only start after the previous transaction is complete, find out the maximum profit that a share trader could have made.
+
+There are various versions of the problem. If we are allowed to buy and sell only once, then we can use Maximum difference between two elements algorithm. If we are allowed to make at most 2 transactions, we can follow approach discussed here. 
+
+In this case, we are only allowed to make at max k transactions. The problem can be solved by using dynamic programming.
+