solve problem Remove Duplicates From Sorted Array

Author: P-ppc

README.md

@@ -121,6 +121,7 @@ All solutions will be accepted!
 |405|[Convert A Number To Hexadecimal](https://leetcode-cn.com/problems/convert-a-number-to-hexadecimal/description/)|[java/py/js](./algorithms/ConvertANumberToHexadecimal)|Easy|
 |796|[Rotate String](https://leetcode-cn.com/problems/rotate-string/description/)|[java/py/js](./algorithms/RotateString)|Easy|
 |844|[Backspace String Compare](https://leetcode-cn.com/problems/backspace-string-compare/description/)|[java/py/js](./algorithms/BackspaceStringCompare)|Easy|
+|26|[Remove Duplicates From Sorted Array](https://leetcode-cn.com/problems/remove-duplicates-from-sorted-array/description/)|[java/py/js](./algorithms/RemoveDuplicatesFromSortedArray)|Easy|
 
 # Database
 |#|Title|Solution|Difficulty|

algorithms/RemoveDuplicatesFromSortedArray/README.md

@@ -0,0 +1,2 @@
+# Remove Duplicates From Sorted Array
+This problem is easy to solve by double pointers

algorithms/RemoveDuplicatesFromSortedArray/Solution.java

@@ -0,0 +1,15 @@
+class Solution {
+    public int removeDuplicates(int[] nums) {
+        if (nums.length == 0) return 0;
+        
+        int pre = 0;
+        
+        for (int i = 0; i < nums.length; i++) {
+            if (i != pre && nums[i] != nums[pre]) {
+                nums[++pre] = nums[i];
+            }
+        }
+        
+        return pre + 1;
+    }
+}

algorithms/RemoveDuplicatesFromSortedArray/solution.js

@@ -0,0 +1,17 @@
+/**
+ * @param {number[]} nums
+ * @return {number}
+ */
+var removeDuplicates = function(nums) {
+    if (nums.length === 0) return 0
+    
+    let pre = 0
+    
+    for (let i = 0; i < nums.length; i++) {
+        if (i !== pre && nums[i] !== nums[pre]) {
+            nums[++pre] = nums[i]
+        }
+    }
+    
+    return pre + 1
+};

algorithms/RemoveDuplicatesFromSortedArray/solution.py

@@ -0,0 +1,17 @@
+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 i != pre and nums[i] != nums[pre]:
+                pre += 1
+                nums[pre] = nums[i]
+                    
+        return pre + 1
+