拼多多算法岗100 100 100 30
第一题用的python内置sort
line = input()
nums = line.split(';')[0]
nums = list(map(int,nums.split(',')))
n = int(line.split(';')[1])
ji = []
ou = []
for num in nums:
if num&1==1:
ji.append(num)
else:
ou.append(num)
ji.sort()
ji.reverse()
ou.sort()
ou.reverse()
if len(ou)>=n:
ans = ou[:n]
else:
ans = ou + ji[:n-len(ou)]
ans = list(map(str,ans))
print (','.join(ans)) 第二题回溯，深度优先搜索 s = int(input())
def cmp(s1,s2):
if len(s1)!=len(s2):
return False
for i in range(len(s1)):
if s1[i]!=s2[i]:
return False
return True
for i in range(s):
nums = [char for char in input()]
news = [char for char in input()]
n = len(nums)
paths = []
def search(nums,luans,news,path,n):
if n == 0:
if cmp(luans,news):
paths.append(path)
return
num = nums[0]
nums = nums[1:]
search(nums,luans,news,path+['d'],n-1)
search(nums,[num]+luans,news,path+['l'],n-1)
search(nums,luans+[num],news,path+['r'],n-1)
search(nums,[],news,[],n)
print ('{')
for path in paths:
print (' '.join(path))
print ('} ') 第三题是dp的思路 n = int(input())#多少骰子
nums = list(map(int,input().split()))#每个骰子的可能结果数
ans = [[0 for i in range(51)] for j in range(50)]#初始化结果
maxnum = 0
for x in range(1,nums[0]+1):#初始化第1次的结果
ans[0][x] = 1
maxnum = max(maxnum,nums[0])
for i in range(1,n):#每个骰子
maxnum = max(maxnum,nums[i])
for j in range(1,maxnum+1):#可能的取值
if nums[i]>=j:#如果当前数值小于当前能取到的最大值
ans[i][j] = sum(ans[i-1][:j+1])+(j-1)*ans[i-1][j]
else:#如果当前数值大于当前能取到的最大值
ans[i][j] = ans[i-1][j] * nums[i]
all_ = 0
all_num = 0
for i in range(1,51):
all_ += ans[n-1][i]
all_num += ans[n-1][i]*i
print ('%.2f'%(all_num/all_)) 第四题leetcode类似题，但是二分查找没实现出来，暴力排序取第k个做的 30%
line = list(map(int,input().split())) n,m,k = line[0],line[1],line[2] ans = [[(i+1)*(j+1) for j in range(m)] for i in range(n)] nums = [] for a in ans: nums.extend(a) nums.sort() nums.reverse() print (nums[k])
