阿里笔试330
感觉自己是个智障，不知道为什么都没有ac，第二题是题目看错了，前面写成所有可能的subset的expectation了。之前没有参加过国内的笔试，求大佬来看看
第一题
import sys
import heapq
n, m, k = 0, 0, 0
farm = {}
if __name__ == "__main__":
# 读取第一行的n
n = 2
ans = 0
for i in range(n):
# 读取每一行
line = sys.stdin.readline().strip()
# 把每一行的数字分隔后转化成int列表
values = list(map(int, line.split()))
if i==0:
n,m,k = values[0],values[1],values[2]
else:
farm = values
heap = []
for i in range(len(farm)):
heapq.heappush(heap,-1*farm[i])
for i in range(1,m+1):
x = heapq.heappop(heap)
x = (x-i*k)/2
x = x+i*k
heapq.heappush(heap,x)
print(heap)
for i in range(len(heap)):
heap[i] -= m*k
print(-1*int(sum(heap))) 第二题
import sys n = 0 input_val = [] if __name__ == "__main__": # 读取第一行的n n = 2 ans = 0 for i in range(n): # 读取每一行 line = sys.stdin.readline().strip() # 把每一行的数字分隔后转化成int列表 values = list(map(int, line.split())) if i==0: n =values[0] else: input_val = values #一个长为n的序列，求随机连续子序列的最大值的期望 #3 #1 2 3 input_val = sorted(input_val) dp = [0]*n dp[0] = 1 for i in range(1,n): if input_val[i]==input_val[i-1]+1: dp[i] = dp[i-1]+1 else: dp[i] = 1 print(dp) sum_val,count_val = 0,0 for i in range(len(dp)): sum_val += dp[i]*input_val[i] count_val += dp[i] print (sum_val/count_val)
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