Remove Duplicates from Sorted Array II - Leetcode 80 - Python
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Problem Link: leetcode.com/problems/remove-...
0:00 - Read the problem
0:30 - Drawing Explanation
9:30 - Coding Explanation
leetcode 80
#neetcode #leetcode #python
Пікірлер: 65
To all those who are just starting their coding journey, you might not understand the code sometimes or even the question. But, that is completely fine. Just stick with it since you have chosen this journey with a purpose and have patience, which in my opinion, is the most important that a programmer must have. Be patient, give yourself time and practice whenever you can.
@floatingfortress721
9 ай бұрын
Well said!
@codeseverywhere
9 ай бұрын
Thank You very much
@user-mw3us5pe2w
5 ай бұрын
thank u, because of that exact same problem i quit leetcode twice before. This time im gonna stick to it no matter wat
@ayojohnson5933
5 ай бұрын
Greatly said!
@user-xo3rj6nh8d
3 ай бұрын
thank you
This solution is kind of a tricky one. I wouldn't be able to come up with this on my own, but yes once you explained it, it makes sense.
@abishekbaiju1705
Жыл бұрын
couldn't agree more.
@leeroymlg4692
Жыл бұрын
that's becoming a pattern the more leetcode questions i come across lol
@nitiandiv
8 ай бұрын
Same thing but in just slight more understanding way var removeDuplicates = function (A) { let pointer = 0; let i = 0; while (i let start = i; while (A[i] == A[i + 1]) { i++; } let end = i; const count = Math.min(2, end - start + 1); for (let x = 0; x A[pointer] = A[end]; pointer++; } i++; } return pointer; };
Even when explained to me as clearly as this, I always find these loops and pointers a complete mind f**k
I feel like ChatGPT's answer is easier to understand on this one. def removeDuplicates(self, nums: List[int]) -> int: left = 2 if len(nums)
@hida-steak-donburi
4 ай бұрын
This solution is amazing... consider it a fixed-length sliding window
@sharaabsingh
3 ай бұрын
Yeah, ChatGPT's solution is much more intuitive and easy to understand. Still thanks for your efforts Neetcode!
@winniethepooh.
Ай бұрын
I agree. It's pretty similar to his solution from his Remove Duplicates from Sorted Array video (kzread.info/dash/bejne/dnl-o7x7oZOsdKQ.html). It was my inital apporach when solving this problem!
@sidazhong2019
9 күн бұрын
well, in similar question #26, you just change every "left - 2" to "left - 1". that work too.
def removeDuplicates(self, nums): j, count = 1, 1 for i in range(1, len(nums)): if nums[i] == nums[i - 1]: count += 1 else: count = 1 if count
Thank you for your efforts for the fellow community !🤟
There is a way simpler solution and more intuitive from my perspective, I can't say that your explanation was really helpful this time, but I really appreciate what you are doing for us. def removeDuplicates(nums: List[int]) -> int: if len(nums)
Thank you so much sir, but could you please combine videos in a playlist so that will be easy for us to follow
In the Constraints: 1
Thanks for the solution. Very easy to follow and reason.
Way easier solution from ChatGPT, easy to understand and much more intuitive class Solution: def removeDuplicates(self, nums: List[int]) -> int: if len(nums)
The fact i can write the solution with O(n^2) but still here to optimize the solution...Thank you bro
Love your videos, they are very insightful and helpful. I'm very greatful for you. I would like this time to share my solution to it, as for the first time ever it has a cleaner approach. Same idea with L and R pointers. with each iteration replace L with R, then check if L is valid, as follows: class Solution: def removeDuplicates(self, nums: List[int]) -> int: l = 2 for r in range(2, len(nums)): nums[l] = nums[r] if nums[l] != nums[l - 2]: l += 1 return l
at 0.55 why is it better to shift the value to the end instead of popping because both have time complexity of O(n)?
well explained helped a lot!
An alternative solution building off of the Remove Duplicates from Sorted Array I solution: class Solution: def removeDuplicates(self, nums: List[int]) -> int: left = 1 freq = 1 for i in range(1, len(nums)): if nums[i] > nums[left - 1]: nums[left] = nums[i] left += 1 freq = 1 elif nums[i] == nums[left - 1] and freq nums[left] = nums[i] left += 1 freq += 1 return left Instead of nested loops I added a var that keeps track of how many times a value is added and an elif that adds up to two of a given value.
You rock!
you make this question hard, you can make it easier by starting left and right from index 2 and if(nums[right ]!==nums[left -2]){ nums[left ]=nums[right ]; we increment left ++ otherwise right ++ , finally return left
I found it easier to use a set to solve this question and the first version of this question as well. I just check if the element we are currently at is already in both sets. If its in neither or in just one of the sets, then I added it to the other set and I swap the element at r and the element at i. But if the element is already in both sets, then I only increment r and don't do any swapping. Here is the code: sett1= set() sett2= set() i = 0 for r in range(len(nums)): if nums[r] not in sett2: if nums[r] not in sett1: #case where its not in either set sett1.add(nums[r]) nums[i], nums[r] = nums[r], nums[i] i+=1 else: #case where its not in set 2 but its in set1 sett2.add(nums[r]) nums[i], nums[r] = nums[r], nums[i] i+=1 #case where its in both sets return i
simpler version: function removeDuplicates(nums: number[]): number { // edge case to return early if 2 or fewer elements if (nums.length
i came up with an NlogN solution but broke my head trying to move the duplicate spots to the end,,,,,this one is very smart :0
is there any reason for not uploading daily challenges ?
My solution is very similar to the 1st version of the problem but with a slight twist. Runtime beats 98% ====================== def removeDuplicates(self, nums: List[int]) -> int: l = 2 flag = 0 for r in range(2, len(nums)): if nums[r] != nums[r-2-flag]: nums[l] = nums[r] l +=1 else: flag +=1 return l
Please make a video on sliding window median
Great work @NeetCodeIO Was thinking you actually stopped uploading daily leetcode video explanations when I didn't get any notification over the past few hours
Super fantastic explanation ,found best algorithm from u ,watched others tutorials but they are just making it complex,it is very easy to solve via your method and also quite easily understandable
There's a bug in this problem(the problem itself, not the solution): It says it wants to remove duplicates in the title and it says in the description that each element will appear *at most* twice. It's quite normal to reason that this means that any element, even which originally has 2 copies of a given value in it, can be trimmed down to 1 copy. But that is forbidden: you have to leave *both* copies in the output for it to be what is expected. So, the description needs to be changed to "at least and at most" twice: If the original has only one of the given, fine; but if it contains two or more copies of the same value, you have to leave at least two in and remove the rest. Of course, the value of k needs to be set to factor this in.
For those, who want a more stricter solution. The relative order is not preserved in this solution, if there are 4 3's [2, 3,3,3,3], we should consider the relative ordering where the first two 3's are considered, but the your solution kinda considers the last occurence of 3.
Thank You for all the videos but what are your thoughts on below solution? I avoid another for loop. I use your r+1 logic. class Solution: def removeDuplicates(self, nums: List[int]) -> int: r=1 while r while r+1
are these questions prasent in NeetCodeAll ?
@shavvasatya7131
Жыл бұрын
Will not prasent 😀
My solution took 50 minutes and 38 lines of code.
Here's the way i did it. maybe it's faster def removeDuplicates(self, nums) -> int: j = 1 for i in range(2,len(nums)): x = nums[i] if x != nums[i-1] or x != nums[i-2]: j += 1 nums[j] = x if i == j + 1 and i + 1 j += 1 return j+1
Can be done in O(n)...
geez before 5m you make this so redundant tbh that removes clarity
my solution : runtime 57 ms. mem 16.64 mb code for n in nums: if nums.count(n)>2: while nums.count(n)>2: nums.remove(n) return len(nums)
class Solution { public: int removeDuplicates(vector& nums) { int len = nums.size(); if (len
Good Evening Sir. I'm an Indian and trying to buy Ur Yearly Plan. I'm getting Ur card is declined. Please help me Sir .. I'm interested to crack MAANG interviews
@NeetCodeIO
Жыл бұрын
Hi, please email me (neetcodebusiness@gmail.com)
# Another Soluion class Solution: def removeDuplicates(self, nums: List[int]) -> int: i = 0 counter = 0 l = len(nums) while i if nums[i] == nums[i+1] and counter == 1: nums.pop(i+1) l -= 1 elif nums[i] == nums[i+1] and counter == 0: counter += 1 i += 1 else: i += 1 counter = 0 return len(nums)
whoever strugle to understand this sol i think this easier to come up with int removeDuplicates(vector& nums) { ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr); if(nums.size()
This is my solution -------------------------------------- class Solution: def removeDuplicates(self, nums: List[int]) -> int: if len(nums) return len(nums) pointer = 2 for num in nums[2:]: if nums[pointer-2] != num: nums[pointer] = num pointer += 1 return pointer -------------------------------------- So basically, if the length of an array is less than 3, obviously everything is already sorted and correctly placed, therefore we just return it. The if condition in the beginning also allows us to start checking from the third element as well. After that we just start checking our current element and the one that is 2 steps behind. If there are equal, it means that the last two elements in the array are already equal to the current one and therefore we cannot place another one (it would be the third). In other cases, it is possible to add another element with the same value
I would rather prefer to use a dictionary & if value for key > 2, pop the value & finally return the len(nums).
There is an easier solution where R (right pointer) loops through the array and just checks whether nums[R] == nums[L] == nums[L-1]. If not: L += 1 nums[L] = nums[R] If yes: continue Return: L+1 JS: var removeDuplicates = function(nums) { if (nums.length let replaceIndex = 1 for (let i = 2 ; i if (nums[i] != nums[replaceIndex] || nums[replaceIndex] != nums[replaceIndex-1]) { replaceIndex++ nums[replaceIndex] = nums[i] } } return replaceIndex+1 };
Doesn't this have a crazy time complexity like O(n^2) or even O(n^3) since he has a nested while loop and a for loop in within it?
l,c = 1,1 for r in range(1,len(nums)): if(nums[r]!=nums[r-1]): c = 1 nums[l]=nums[r] l += 1 else: if c
Todays Daily Challenge?
🙆♂️
An even more intuitive solution. O(n) class Solution: def removeDuplicates(self, nums: List[int]) -> int: if len(nums) == 1: return l = 0 r = 0 while r # edge case if l == 0 and nums[l+1] == nums[l]: # skip the first value to continue as usual r+=1 l+=1 if nums[r] != nums[l]: l+=1 nums[l] = nums[r] # Greedily check for one more duplicate as it is two # if we get it we change else no problem. if r+1 l+=1 nums[l] = nums[r] r+=1 r+=1 return l+1
This is nice solution