Create remove-duplicates-from-sorted-array-ii.cpp

Author: kamyu104

C++/remove-duplicates-from-sorted-array-ii.cpp

@@ -0,0 +1,27 @@
+// Time:  O(n)
+// Space: O(1)
+
+class Solution {
+public:
+    int removeDuplicates(vector<int>& nums) {
+        if (nums.empty()) {
+            return 0;
+        }
+
+        const int k = 2; // At most k duplicated.
+
+        int left = 0;
+        int right = 1;
+
+        while (right < nums.size()) {
+            if (nums[left] != nums[right] ||
+                (left - k + 1 < 0 || nums[left] != nums[left - k + 1])) {
+                ++left;
+                nums[left] = nums[right];
+            }
+            ++right;
+        }
+
+        return left + 1; 
+    }
+};