Im new to leet code
#๐ Problems with leet code
hybrid umbra
neat coral
@hybrid umbra which question
neat coral
hmm
neat coral
you know return function ?
hybrid umbra
you know return function ?
yes
neat coral
you should not print them
you should return the answer in leetcode for the answer to be matched
check it
return it as a list
neat coral
yea, if you want output then you need to print it separately but to pass the test case you need to return the value
coz basically on the other end
the function is run
hybrid umbra
nums = input()
target = input()
class Solution(object):
def twoSum(self, nums, target):
for idx1 in range(0, len(nums)):
val = nums[idx1]
for idx2 in range(idx1 + 1, len(nums)):
val2 = nums[idx2]
if val + val2 == target:
return [idx1, idx2]
Solution().twoSum(nums, target)
this is my full code
hybrid umbra
Oh wait
neat coral
also
gilded folio
```py
nums = input()
target = input()
class Solution(object):
def twoSum(se...
You aren't supposed to have those inputs or the last line
neat coral
the num and range is inputed by leetcode not you
real sandal
calling Solution at the end wouldn't even call the method
so it's really doing nothing
hybrid umbra
Leet code does stuff in the background?
neat coral
Leet code does stuff in the background?
in the backend yes
real sandal
well yeah, cuz it has to test stuff
neat coral
so basically this is what you neeeded to do
hybrid umbra
ohh i never knew that, i thought we had to get all the inputs and call the functions
neat coral
how you get it
hybrid umbra
That makes al ot of sense thank you
hybrid umbra
yep ty
neat coral
so it runs all the xyz test cases, which include all the test cases and everything
edge cases and all
welcome
you are smart btw
hybrid umbra
so it runs all the xyz test cases, which include all the test cases and everythi...
๐ ๐ ty so much
neat coral
coz when i started leetcode i didnt know what a class was and how to exexute you own class funcs and what self was
neat coral
๐ ๐ ty so much
keep it up, and how advanced are you in programming, like you migrating from other language?
hybrid umbra
keep it up, and how advanced are you in programming, like you migrating from oth...
ty :D i only know how to code python
neat coral
ty :D i only know how to code python
have you come across data structs and algo?
hybrid umbra
have you come across data structs and algo?
ive done aiosqlite and SQL
as well as json
neat coral
okay, just telling you thing coz i would have wished for the same advice
learn some basics of what is time complexity and space complexity
hybrid umbra
in terms of optimising the code?
neat coral
yea
hybrid umbra
so basically this is what you neeeded to do
oh yh ill prob try rewriting this code because it uses nested loops
neat coral
and use neetcode .io to look for different solutions, for python there are videos
hybrid umbra
ill look into it ty
elfin viper
there is also rosetta code
neat coral
oh yh ill prob try rewriting this code because it uses nested loops
when you do message me the code, i wanna see how you solve it as a new dude
neat coral
there is also rosetta code
oh
elfin viper
often rosstta code has the alternate versions of code that are more effiecent
neat coral
sometimes i see some crazy code on leetcode like these
this one is for reversing a linked list
elfin viper
funniest one ive seen is sleep sort
neat coral
this is the least memory taxing sol
but how does one even think of these
and is it even useful learning these
hybrid umbra
when you do message me the code, i wanna see how you solve it as a new dude
Sure
im trying to find a different way now
neat coral
yea, there is a really nice way to solve this, one you hear it (i this case read it) you wont be able to forget it
you wanna know or you wanna try for yourself?
@hybrid umbra
hybrid umbra
im thinking of enumerate
neat coral
there is a waaaaaaaaaaaaaaaaay better sol
hybrid umbra
how else would you do it?
elfin viper
list2 = [3,2,1,4,5,6,7,8,9,10]
def sleep_sort(val):
import time
import threading
## create 1 thread for each value
for i in val:
threading.Thread(target=lambda i=i: (time.sleep(i), print(i))).start()
## get the thread to wait for all threads to finish
## get
time.sleep(max(val)+1)
sleep_sort(list2)```baiscaly you create a thread for each element, then sleep basied on the value of the element, the return will be naturaly sorted ;
neat coral
yea so you run a for loop across the list's range
then which ever element you are in ->you search for the number that is (target-element) you are in
hybrid umbra
yea so you run a for loop across the list's range
then which ever element you ar...
ohh
but wouldnt that cause
problems
with duplicate numbers
elfin viper
that and it takes time N to work
hybrid umbra
and yo uwould need to prevent it from checking the same numbre
elfin viper
and yo uwould need to prevent it from checking the same numbre
dosnt matter if your only searching for unqiue elments
so yeah it natrualy gives you unqiue sorted list
but honestly this is such a dumb algorithm for many many reasons
not only the fact its On time but all On threads
elfin viper
O notation is used to denote complexity in both time and calualtion
n being the number of elments in the list
the advantage i guess is it runs in liner time vs o^n time like going though a for loop for the lenght of N would
https://www.youtube.com/watch?v=cWHTyeQg79A, you know this part
"general soultion in polynomial time" big O notation is baiscaly what hes talking about
neat coral
finally @hybrid umbra
i couldnt remember the prev logic
neat coral
yea, there is a really nice way to solve this, one you hear it (i this case read...
so this is false
class Solution:
def twoSum(self, nums: List[int], target: int) -> List[int]:
ind=-1
numlist=nums
while len(nums)>1:
ind=ind+1
first=nums[0]
numlist.pop(0)
if (target-first) in numlist:
return [ind, numlist.index(target-first)+ind+1]
return None
still this is slow for some reason...
i remember it now
this is it
class Solution:
def twoSum(self, nums: List[int], target: int) -> List[int]:
his={} #his as history
for i, num in enumerate(nums):
x= target - num #x is the valuw we have to find
if x in his:
return [his[x],i]
his[num]=i
try this
def two_sum2(nums, target):
nums.sort()
half_target = target / 2
mid_index = len(nums) // 2
mid_value = nums[mid_index]
if mid_value > half_target:
search_range = nums[:mid_index]
else:
search_range = nums[mid_index:]
for i in range(len(search_range)):
for j in range(i+1, len(search_range)):
if search_range[i] + search_range[j] == target:
return [nums.index(search_range[i]), nums.index(search_range[j])]
return None
print(two_sum2([2, 7, 11, 15], 9))```run that though the profiler ๐
neat coral
ohkay one sec
elfin viper
yeah i just realised its kinda a mental test
elfin viper
def two_sum2(nums, target):
indexed_nums = list(enumerate(nums))
indexed_nums.sort(key=lambda x: x[1])
left, right = 0, len(indexed_nums) - 1
while left < right:
current_sum = indexed_nums[left][1] + indexed_nums[right][1]
if current_sum == target:
return [indexed_nums[left][0], indexed_nums[right][0]]
elif current_sum < target:
left += 1
else:
right -= 1
return None
@hybrid umbra also when you click on the bar graph's bar you can see their sample code
elfin viper
[0, 1] [1, 2] [0, 1]
elfin viper
i am good at math
neat coral
i would love to if you can spare some of your time?
you aint busy right?
elfin viper
ok so what it does, is take the taget value
half it
then it sorts the list
then searches from the midpoint of the list in steps of log2 from the middle of the list
then it has to check the poistion of the new sorted list vs the orginal
and return the values of the orginal list
poitional values
pythons good at list sorting timewise
so its a time effient but not memory effieent method
neat coral
im just awestruck that you have such knowledge of which takes how much time
elfin viper
experaince
and yeah its dealing with shit like leetcode and testing time
also i deal with big data, sooo i have spent way too much time optimizing code
neat coral
you work in a job or solo dev?
elfin viper
looking for work, just finished my AI masters
neat coral
pythons good at list sorting timewise
which are the things that it is not good at?
elfin viper
quite alot, however my issue was mainly with stuff like apache spark
neat coral
https://tenor.com/view/monkey-talk-monkey-kisarazu-monkey-brain-monkey-monkey-and-human-gif-26698951
elfin viper
there is a python rprofiler tool built in
spend some time with it you will see whats fast whats not
neat coral
mind if i chat with you for a while in DMS @elfin viper
neat coral
spend some time with it you will see whats fast whats not
yes sir
elfin viper
sometime tommrow good? rn i am dealing with making a AI model for alot of data
neat coral
oh sure sure
ill just ping you in chat and type my stuff, reply to it whenever you can in this week
astral hedgeBOT
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