记录了初步解题思路 以及本地实现代码；并不一定为最优 也希望大家能一起探讨 一起进步
目录
1/1 1599. 经营摩天轮的最大利润
def minOperationsMaxProfit(customers, boardingCost, runningCost):
"""
:type customers: List[int]
:type boardingCost: int
:type runningCost: int
:rtype: int
"""
if 4*boardingCost<runningCost:
return -1
wait = 0
ans = -1
cur = -999
maxv = -999
num = 0
for cus in customers:
wait += cus
tmp = min(4,wait)
wait -=tmp
cur += tmp*boardingCost-runningCost
num +=1
if cur>maxv:
maxv = cur
ans = num
while wait>0:
tmp = min(4,wait)
wait -=tmp
cur += tmp*boardingCost-runningCost
num +=1
if cur>maxv:
maxv = cur
ans = num
return ans
1/2 466. 统计重复个数
def getMaxRepetitions(s1, n1, s2, n2):
"""
:type s1: str
:type n1: int
:type s2: str
:type n2: int
:rtype: int
"""
if n1==0:
return 0
s1cnt,ind,s2cnt = 0,0,0
m = {}
while True:
s1cnt +=1
for c in s1:
if c==s2[ind]:
ind+=1
if ind==len(s2):
s2cnt+=1
ind=0
if s1cnt==n1:
return s2cnt//n2
if ind in m:
s1p,s2p = m[ind]
pre = (s1p,s2p)
nxt =(s1cnt-s1p,s2cnt-s2p)
break
else:
m[ind] = (s1cnt,s2cnt)
ans = pre[1]+(n1-pre[0])//(nxt[0])*nxt[1]
l = (n1-pre[0])%nxt[0]
for i in range(l):
for c in s1:
if c==s2[ind]:
ind+=1
if ind==len(s2):
ans+=1
ind=0
return ans//n2
1/3 2487. 从链表中移除节点
class ListNode(object):
def __init__(self, val=0, next=None):
self.val = val
self.next = next
def removeNodes(head):
"""
:type head: Optional[ListNode]
:rtype: Optional[ListNode]
"""
def do(node):
if node is None:
return None
node.next = do(node.next)
if node.next and node.val<node.next.val:
return node.next
else:
return node
return do(head)
1/4 2397. 被列覆盖的最多行数
def maximumRows(matrix, numSelect):
"""
:type matrix: List[List[int]]
:type numSelect: int
:rtype: int
"""
m,n=len(matrix),len(matrix[0])
mask = [sum(v<<j for j,v in enumerate(row)) for i,row in enumerate(matrix)]
ans,limit = 0,1<<n
for cur in range(1,limit):
if cur.bit_count()!=numSelect:
continue
t = sum((mask[j]&cur)==mask[j] for j in range(m))
ans = max(ans,t)
return ans
1/5 1944. 队列中可以看到的人数
def canSeePersonsCount(heights):
"""
:type heights: List[int]
:rtype: List[int]
"""
st=[]
n = len(heights)
ans = [0]*n
for i in range(n-1,-1,-1):
cur = heights[i]
while st and cur>st[-1]:
ans[i]+=1
st.pop()
if st:
ans[i]+=1
st.append(cur)
return ans
1/6 2807. 在链表中插入最大公约数
class ListNode(object):
def __init__(self, val=0, next=None):
self.val = val
self.next = next
def insertGreatestCommonDivisors(head):
"""
:type head: Optional[ListNode]
:rtype: Optional[ListNode]
"""
import math
node = head
while node.next is not None:
node.next = ListNode(math.gcd(node.val, node.next.val), node.next)
node = node.next.next
return head
1/7 383. 赎金信
def canConstruct(ransomNote, magazine):
"""
:type ransomNote: str
:type magazine: str
:rtype: bool
"""
if len(magazine)<len(ransomNote):
return False
from collections import defaultdict
m = defaultdict(int)
for c in magazine:
m[c]+=1
for c in ransomNote:
m[c]-=1
if m[c]<0:
return False
return True
