627. Swap Salary

👩‍💻 문제

 

Write a solution to swap all 'f' and 'm' values (i.e., change all 'f' values to 'm' and vice versa) with a single update statement and no intermediate temporary tables. Note that you must write a single update statement, do not write any select statement for this problem. The result format is in the following example.

Example 1:
Input: 
Salary table:
+----+------+-----+--------+
| id | name | sex | salary |
+----+------+-----+--------+
| 1  | A    | m   | 2500   |
| 2  | B    | f   | 1500   |
| 3  | C    | m   | 5500   |
| 4  | D    | f   | 500    |
+----+------+-----+--------+
Output: 
+----+------+-----+--------+
| id | name | sex | salary |
+----+------+-----+--------+
| 1  | A    | f   | 2500   |
| 2  | B    | m   | 1500   |
| 3  | C    | f   | 5500   |
| 4  | D    | m   | 500    |
+----+------+-----+--------+

 

💡 풀이

import pandas as pd

def swap_salary(salary: pd.DataFrame) -> pd.DataFrame:
    salary.update(salary['sex'].map(lambda x : 'm' if x=='f' else 'f'))
    return salary

 

✍️ 해설

update 기능을 몰랐다 ...? 세상에나

map 안에 lambda 처리로 m은 f로 바꾸고, f는 m으로 바꾸는 처리를 해줄 수 있다