Completed TwoPointer2

Solutions.py

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+Problem1 (https://leetcode.com/problems/remove-duplicates-from-sorted-array-ii/)
+Time Complexity : O(n)
+Space Complexity : O(1)
+
+## we count the duplicates that are allowed
+## if the count increases we replace and move the slow pointer
+
+class Solution(object):
+    def removeDuplicates(self, nums):
+        """
+        :type nums: List[int]
+        :rtype: int
+        """
+        slow =1 
+        count =1
+
+        for i in range(1,len(nums)):
+            if nums[i] == nums[i-1]:
+                count+=1
+            else:
+                count =1
+            if count <=2:
+                nums[slow] = nums[i]
+                slow +=1
+
+        return slow
+
+
+
+Problem2 (https://leetcode.com/problems/merge-sorted-array/)
+Time Complexity : O(n)
+Space Complexity : O(1)
+
+
+## start filling nums1 from backwards
+## how to fill check which one is bigger, fill with the bigger element and decrease the pointers
+## Once completed check if anything remaining in p2, fill it without checking anything and decrease pointer
+class Solution(object):
+    def merge(self, nums1, m, nums2, n):
+        """
+        :type nums1: List[int]
+        :type m: int
+        :type nums2: List[int]
+        :type n: int
+        :rtype: None Do not return anything, modify nums1 in-place instead.
+        """
+        p1 = m-1
+        p2= n-1
+        idx = m+n-1
+        while p1>=0 and p2>=0:
+            if nums1[p1] > nums2[p2]:
+                nums1[idx] = nums1[p1]
+                p1-=1
+
+            else:
+                nums1[idx] = nums2[p2]
+                p2-=1
+            idx-=1
+        while p2>=0:
+            nums1[idx] = nums2[p2]
+            p2-=1
+            idx-=1
+
+
+
+
+
+
+Problem3 (https://leetcode.com/problems/search-a-2d-matrix-ii/)
+Time Complexity : O(n)
+Space Complexity : O(1)
+
+## I can start from the top right corner or bottom left to perform the steps
+## check if cur == target return else move left or right
+
+
+
+class Solution(object):
+    def searchMatrix(self, matrix, target):
+        """
+        :type matrix: List[List[int]]
+        :type target: int
+        :rtype: bool
+        """
+
+        def helper(i,j):
+
+            ## base condition to exit
+            if i<0 or i>=rows or j<0 or j>=cols:
+                return False
+            ## returning true if found
+            if matrix[i][j] == target:
+                return True
+
+            ## moving left
+            elif matrix[i][j] > target:
+                return helper(i,j-1)
+            ## moving right
+            else:
+                return helper(i+1,j)
+
+        rows = len(matrix)
+        cols = len(matrix[0])
+
+        return helper(0,cols-1)
+
+