题解 | #统计运动会项目报名人数(二)#
统计运动会项目报名人数(二)
https://www.nowcoder.com/practice/737d224c9cce482fb56ff812d04e79ab
import pandas as pd items = pd.read_csv('items.csv') signup = pd.read_csv('signup.csv') merge_si = pd.merge(items,signup,how='left',on='item_id') res = merge_si.groupby(['item_name']).name.count().fillna(0) print(res)