我正在嘗試使用 for 循環在字典中查找輸入值的平均值？

Question

if __name__ == '__main__':
n = int(input())
student_marks = {}
for _ in range(n):
    name, *line = input().split()
    scores = list(map(float, line))
    student_marks[name] = scores
query_name = input()
sum=0
if query_name in student_marks:
    for i in student_marks[query_name]:
        sum+=i
    x=float(sum/len(scores))
    print("%.2f"%x)

我已經這樣做了，但想以更少的行數執行

Answer 1

您可以將求和循環替換為：

if query_name in student_marks:
  total = sum(student_marks[query_name])
  mean = total / len(student_marks[query_name])
  print("%.2f" % mean)

您還可以預先計算每個學生的平均值並將其存儲在該字典中以開始：

for _ in range(n):
  name, *line = input().split()
  record = {'scores': list(map(float, line))}
  record['total'] = sum(record['scores'])
  record['n'] = len(record['scores'])
  student_marks[name] = record

或者：

for _ in range(n):
  name, *line = input().split()
  scores = list(map(float, line))
  student_marks[name] = {
    'scores': scores,
    'total': sum(scores),
    'n': len(scores)
  }

那么您的查詢將如下所示：

def query(name):
  if name in student_marks:
   record = student_marks[name]
   return record['total'] / record['n']