better solution of Remove Duplicates From Sorted Array

Author: P-ppc

algorithms/RemoveDuplicatesFromSortedArray/README.md

@@ -1,2 +1,21 @@
 # Remove Duplicates From Sorted Array
-This problem is easy to solve by double pointers
+This problem is easy to solve by double pointers, like below:
+```python
+class Solution(object):
+    def removeDuplicates(self, nums):
+        """
+        :type nums: List[int]
+        :rtype: int
+        """
+        if len(nums) == 0:
+            return 0
+        
+        pre = 0
+        for i in range(len(nums)):
+            if nums[i] != nums[pre]:
+                pre += 1
+                nums[pre] = nums[i]
+                    
+        return pre + 1
+        
+```