# \[LeetCode] 26. Remove Duplicates from Sorted Array

Given a sorted array *nums*, remove the duplicates [**in-place**](https://en.wikipedia.org/wiki/In-place_algorithm) such that each element appear only *once* and return the new length.

Do not allocate extra space for another array, you must do this by **modifying the input array** [**in-place**](https://en.wikipedia.org/wiki/In-place_algorithm) with O(1) extra memory.

**Example 1:**

```
Given nums = [1,1,2],

Your function should return length = 2, with the first two elements of nums being 1 and 2 respectively.

It doesn't matter what you leave beyond the returned length.
```

**Example 2:**

```
Given nums = [0,0,1,1,1,2,2,3,3,4],

Your function should return length = 5, with the first five elements of nums being modified to 0, 1, 2, 3, and 4 respectively.

It doesn't matter what values are set beyond the returned length.
```

**Clarification:**

Confused why the returned value is an integer but your answer is an array?

Note that the input array is passed in by **reference**, which means modification to the input array will be known to the caller as well.

Internally you can think of this:

```
// nums is passed in by reference. (i.e., without making a copy)
int len = removeDuplicates(nums);

// any modification to nums in your function would be known by the caller.
// using the length returned by your function, it prints the first len elements.
for (int i = 0; i < len; i++) {
    print(nums[i]);
}
```

**Analyse:**

​

**Solution:**

```swift
class Solution {
    
    func removeDuplicates(_ nums: inout [Int]) -> Int {
        var length = 0;
        var current = 99999;

        var i = 0;
        while(i<nums.count) {
            if(current != nums[i]) {
                length += 1;
                current = nums[i];
                i += 1;
            }
            else {
                nums.remove(at: i)
            }
        }
        
        return length;
    }
}
```

\
**Solution2:**

```
class Solution {
    func removeDuplicates(_ nums: inout [Int]) -> Int {
        
        var currentValue: Int = 0
        var list: [Int] = []
        
        for i in 0..<nums.count {
            let num = nums[i]
            
            if(list.count == 0) {
                currentValue = num 
                list.append(num)
                continue
            }
            
            if(num == currentValue) {
                continue
            } else {
                 currentValue = num 
                list.append(num)
            }
        }
        
        nums = list
        return nums.count
    }
}
```