第 80 场双周赛(python版)

 按照题意模拟就行

class Solution:
    def strongPasswordCheckerII(self, password: str) -> bool:
        # T="!@#$%^&*()-+"
        if len(password)<8:
            # print(1)
            return False
        a=b=c=d=0
        for letter in password:
            # print(letter)
            if letter.islower():
                a=1
            if letter.isupper():
                b=1
            if letter.isdigit():
                c=1
            if (letter in "!@#$%^&*()-+"):
                d=1
        # print("num")
        # print(a,b,c,d)
        if (a+b+c+d)!=4:
            # print(2)
            return False
        for i in range(1,len(password)):
            if password[i]==password[i-1]:
                # print(3)
                return False
        return True

 二分答案

class Solution:
    def successfulPairs(self, spells: List[int], potions: List[int], success: int) -> List[int]:
        ls=len(spells)
        lp=len(potions)
        potions.sort()
        ans=[]
        for i,num in enumerate(spells):
            # print((i,num))
            l=0
            r=lp-1
            p=lp
            while l<=r:
                mid=(l+r)//2
                if(num*potions[mid]>=success):
                    p=mid
                    r=mid-1
                else:
                    l=mid+1
            ans.append(lp-p)
        return ans

大力出奇迹！

默认字典collections.defaultdict()的使用：

https://blog.csdn.net/weixin_44110891/article/details/89575020

import collections
from typing import *

class Solution:
    def matchReplacement(self, s: str, sub: str, mappings: List[List[str]]) -> bool:
        dict=collections.defaultdict(set)
        for x in mappings:
            dict[x[0]].add(x[1])
        def check(s1,s2):#s1:原串 s2:比较串
            for i in range(0,len(s1)):
                if(s1[i]!=s2[i]) and ((s2[i] not in dict )or (s1[i] not in dict[s2[i]])):
                    return False
            return True
        for i in range(0,(len(s))):
            # if (i + len(sub)-1 < len(s)):
            #     print(s[i:i+len(sub)])
            if (i+len(sub)-1<len(s)) and check(s[i:i+len(sub)],sub):
                return True
        return False

 双指针+前缀和

import collections
from typing import *

class Solution:
    def countSubarrays(self, nums: List[int], k: int) -> int:
        ans=0
        l=0
        r=0
        sum=0
        while r<len(nums):
            sum+=nums[r]
            while (r-l+1)*sum>=k:
                sum-=nums[l]
                l+=1
            ans+=r-l+1
            r=r+1
        return ans