upload on 3/20

Author: gyb1325

151. Reverse Words in a String.py

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+class Solution:
+
+    def reverseWords(self, s: str) -> str:
+        return " ".join(s.strip().split()[::-1])

152. Maximum Product Subarray.py

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+class Solution:
+
+    def maxProduct(self, nums: List[int]) -> int:
+        cur_min = nums[0]
+        cur_max = nums[0]
+        max_overall = nums[0]
+        for num in nums[1:]:
+            cur_min, cur_max = min(cur_min * num, cur_max * num, num), max(cur_min * num, cur_max * num, num)
+            max_overall = max(cur_max, max_overall)
+        return max_overall

153. Find Minimum in Rotated Sorted Array.py

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+class Solution:
+
+    def findMin(self, nums: List[int]) -> int:
+        left = 0
+        right = len(nums) - 1
+        temp = nums[0]
+        while left < right:
+            mid = left + (right - left) // 2
+            if nums[mid] < nums[right]:
+                right = mid
+            elif nums[mid] > nums[right]:
+                left = mid + 1
+            else:
+                right -= 1
+        return nums[left]
+        # May a little bit faster
+        # left = 0
+        # right = len(nums) - 1
+        # temp = nums[0]
+        # while left < right and nums[left] >= nums[right]:
+        #     mid = left + (right - left) // 2
+        #     if nums[mid] < nums[right]:
+        #         right = mid
+        #     elif nums[mid] > nums[right]:
+        #         left = mid + 1
+        #     else:
+        #         right -=1
+        #         left += 1
+        # return nums[left]

154. Find Minimum in Rotated Sorted Array II.py

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+class Solution:
+
+    def findMin(self, nums: List[int]) -> int:
+        left = 0
+        right = len(nums) - 1
+
+        while left < right:
+            mid = left + (right - left) // 2
+            if nums[mid] <= nums[right]:
+                right = mid
+            else:
+                left = mid + 1
+        return nums[left]

155. Min Stack.py

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+class MinStack:
+
+    def __init__(self):
+        """
+        initialize your data structure here.
+        """
+        self.min_val = float("inf")
+        self.stack = []
+
+    def push(self, x: int) -> None:
+        if x <= self.min_val:
+            self.stack.append(self.min_val)
+            self.min_val = x
+        self.stack.append(x)
+
+    def pop(self) -> None:
+        if (self.stack.pop() == self.min_val):
+            self.min_val = self.stack.pop()
+
+    def top(self) -> int:
+        return self.stack[-1]
+
+    def getMin(self) -> int:
+        return self.min_val
+
+
+# Your MinStack object will be instantiated and called as such:
+# obj = MinStack()
+# obj.push(x)
+# obj.pop()
+# param_3 = obj.top()
+# param_4 = obj.getMin()

162. Find Peak Element.py

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+class Solution:
+
+    def findPeakElement(self, nums: List[int]) -> int:
+        left = 0
+        right = len(nums) - 1
+        while left < right:
+            mid = left + (right - left) // 2
+            if nums[mid] > nums[mid + 1]:
+                right = mid
+            else:
+                left = mid + 1
+        if nums[left] > nums[right]:
+            return left
+        else:
+            return right