题解 | 多报名表的运动项目人数统计

import pandas as pd

items = pd.read_csv('items.csv')

signup = pd. read_csv('signup.csv')

signup1 = pd.read_csv('signup1.csv')

sign = pd.concat([signup,signup1],ignore_index=True)

total = pd.merge(items,sign,on='item_id',how='left')

data = total.groupby(by='item_name')['employee_id'].apply('count')

item_data= data[data!=0]
print(item_data)