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# 01/17/2022 27

When we encounter nums\[i] = valnums\[i]=val, we can swap the current element out with the last element and dispose the last one, else increment the i, finally return n.

Time O(n)

Space O(1)

class Solution { 

public int removeElement(int\[] nums, int val) { 

int i = 0; 

int n = nums.length; 

while (i < n){ if(nums\[i] == val){&#x20;

nums\[i] = nums\[n-1];

&#x20;n--;&#x20;

}else{&#x20;

i++; }&#x20;

} return n; }

![](/files/4gkp1Hoxw0fVaDGNkuLa)