持續更新
def
quick_rank
(nums):if
len(nums)
<=1:
return nums
left,right =
,[] mid = nums[0]
for i in nums[1:
]:if i > mid:
else
:return quick_rank(left)
+[mid]
+quick_rank(right)
def
binary_search
(nums,target)
: left,right =0,
len(nums)-1
while left <= right:
mid =
(left+right)//2
if nums[mid]
== target:
return mid
if nums[mid]
< target:
left = mid +
1else
: right = mid -
1return
-1
def
pa_stairs
(n):
if n ==1:
return
1if n ==2:
return
2 a,b =1,
2for _ in
range(2
,n):
a,b = b,a+b
return b
def
sum_of_two
(nums,target)
: dic =
for i in
range
(len
(nums)):
cur = target - nums[i]
if cur in dic.keys():
return
[dic[cur]
,i]else
: dic[nums[i]
]= i
return
def
max_drawdown
(nums):if
len(nums)==1
:return nums[-1
] re =
float
('-inf'
) min_x = nums[-1
]for i in
range
(len
(nums)-2
,-1,
-1):
min_x =
min(nums[i]
,min_x)
re =
max(nums[i]
-min_x,re)
return re
def
merge_sorted_array
(a,b)
: re =
while a and b:
if a[0]
> b[0]
:0))
else:0
))if a:
re.extend(a)
else
: re.extend(b)
return re
def
max_sub
(nums)
: n =
len(nums)
if n ==1:
return nums[0]
dp,re = nums[0]
,nums[0]
for i in
range(1
,len
(nums)):
dp =
max(nums[i]
,dp+nums[i]
) re =
max(re,dp)
return re
def
longest_substr
(s):
n =len(s)
if n ==1:
return s
left,right =0,
1 memo =
set(s[0]
) re = s[0]
while left <= right and right < n:
if s[right]
notin memo:
memo.add(s[right]
) right +=
1 cur = s[left:right]
iflen
(cur)
>
len(re)
: re = cur
else
: memo.remove(s[left]
) left +=
1return re
def
permutations
(nums)
: re =
n =len(nums)
if n ==1:
return
[nums]
defhelper
(nums,temp):if
not nums:
if temp not
in re:
return
for i in
range
(len
(nums)):
helper(nums[
:i]+nums[i+1:
],temp +
[nums[i]])
helper(nums,
)return re
def
sum_of_three
(nums,target)
: nums =
sorted
(nums)
n =len(nums)
re =
for k,v in
enumerate
(nums)
: i,j = k+
1,n-
1while iif v+nums[i]
+nums[j]
< target:
i +=
1elif v+nums[i]
+nums[j]
> target:
j -=
1else
:(v,nums[i]
,nums[j]))
i,j = i+
1,j-
1return re
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