07-Remove-Duplicates-from-Sorted-Array.md

Remove Duplicates from Sorted Array

Problem Link

https://leetcode.com/problems/remove-duplicates-from-sorted-array/

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Pattern

• Two Pointer

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Approach

Use two pointers: one for the place to write unique elements, the other to scan.

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Time Complexity

O(n)

Space Complexity

O(1)

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Java Solution

class Solution {
    public int removeDuplicates(int[] nums) {
        if (nums.length == 0) return 0;
        int idx = 0;
        for (int i = 1; i < nums.length; i++) {
            if (nums[i] != nums[idx]) nums[++idx] = nums[i];
        }
        return idx + 1;
    }
}