solve problem Best Time To Buy And Sell Stock II

Author: P-ppc

README.md

@@ -88,6 +88,7 @@ All solutions will be accepted!
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algorithms/BestTimeToBuyAndSellStockII/README.md

@@ -0,0 +1,2 @@
+# Best Time To Buy And Sell Stock
+This problem is easy to solve

algorithms/BestTimeToBuyAndSellStockII/Solution.java

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+class Solution {
+    public int maxProfit(int[] prices) {
+        Integer currentStock = null;
+        int maxProfit = 0;
+        
+        for (int i = 0; i < prices.length; i++) {
+            if (currentStock == null && i + 1 < prices.length && prices[i + 1] > prices[i]) {
+                currentStock = prices[i];
+            } else if (currentStock != null && ((i + 1 < prices.length && prices[i + 1] < prices[i]) || i + 1 == prices.length)) {
+                maxProfit += prices[i] - currentStock;
+                currentStock = null;
+            }
+        }
+        
+        return maxProfit;
+    }
+}

algorithms/BestTimeToBuyAndSellStockII/solution.js

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+/**
+ * @param {number[]} prices
+ * @return {number}
+ */
+var maxProfit = function(prices) {
+    let currentStock = null,
+        maxProfit = 0
+    
+    for (let i = 0; i < prices.length; i++) {
+        if (currentStock === null && i + 1 < prices.length && prices[i + 1] > prices[i]) {
+            currentStock = prices[i]
+        } else if (currentStock !== null && ((i + 1 < prices.length && prices[i + 1] < prices[i]) || i + 1 === prices.length)) {
+            maxProfit += prices[i] - currentStock
+            currentStock = null
+        }
+    }
+    
+    return maxProfit
+};

algorithms/BestTimeToBuyAndSellStockII/solution.py

@@ -0,0 +1,19 @@
+class Solution(object):
+    def maxProfit(self, prices):
+        """
+        :type prices: List[int]
+        :rtype: int
+        """
+        current_stock = None
+        max_profit = 0
+        
+        for i in range(0, len(prices)):
+            # buy
+            if current_stock == None and i + 1 < len(prices) and prices[i + 1] > prices[i]:
+                current_stock = prices[i]
+            # sell
+            elif current_stock != None and ((i + 1 < len(prices) and prices[i + 1] < prices[i]) or i + 1 == len(prices)):
+                max_profit += prices[i] - current_stock
+                current_stock = None
+        
+        return max_profit