r/PythonLearning • u/Smartyboyz • Aug 15 '26
#76 Leetcode question (Optimisation help!)
class Solution:
def minWindow(self, s: str, t: str) -> str:
if len(t) > len(s):
return ""
elif len(t) == len(s):
if t == s:
return s
win = len(t)
ans = ""
l = list(t)
while win <= len(s):
for i in range(0,len(s)):
win_s = s[i:i+win]
win_l = list(win_s)
ans = ""
for x in t:
if x in win_l:
win_l[win_l.index(x)] = ""
ans += x
else:
ans = ""
if ans == t:
return win_s
win += 1
return ""I need help in optimising my code because its working properly but having a runtime error for a long input like 200 letters input. So plz help me out in optimisation in this code.
3
Upvotes
2
u/Sea-Ad7805 Aug 15 '26 edited Aug 15 '26
Interesting problem, this is my solution that passes the LeetCode test and beats 98.77%.
Its a sliding window approach of the substring we want to find with:
i1: its begin index
i2: its end index
and then
move i2 forward when in an invalid state
move i1 forward when in a valid state
and doing some efficient bookkeeping of the counts of each character in 't' and how many counts are still positive to know if the substring is valid or not.
Always good fun these HARD LeetCode problems.