Remove Element

 1 class Solution  2 { 3 public: 4     int removeElement(vector<int>& nums, int val)  5     { 6         int len = nums.size(); 7         int i = 0; 8         while(i < len) 9             nums[i] == val? (nums[i] = nums[--len]): ++i;10         return len;11     }12 };

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