20260221 TIL

[Today I Learn]

- SQL codekata

- Python codekata

- 오늘 배운 세션

- 오늘 배운 미니세션

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[SQL codekata]

- 문제 1.

1. 문제 링크: https://www.hackerrank.com/challenges/weather-observation-station-13/problem

2. 정답 코드

select round(sum(lat_n),4) 
from station
where lat_n > 38.7880 and lat_n < 137.2345

 

- 문제 2.

1. 문제 링크: https://www.hackerrank.com/challenges/weather-observation-station-14/problem

2. 정답 코드

select round(max(lat_n),4)
from station 
where lat_n < 137.2345

 

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[Python codekata] 

- 문제 1.

1. 문제 링크: https://school.programmers.co.kr/learn/courses/30/lessons/120811?language=python3

2. 정답 코드

def solution(array):
    ind = int(len(array)/2)
    array.sort()
    return array[ind]

def solution(array):
    return sorted(array)[len(array)//2]

def solution(array):
    array.sort()
    return array[len(array)//2]

 

- 문제 2.

1. 문제 링크: https://school.programmers.co.kr/learn/courses/30/lessons/120813

2. 정답 코드

def solution(n):
    answer = [i for i in range(n+1) if i % 2 != 0]
    return answer

def solution(n):
    answer = [i for i in range(n+1) if i % 2]
    return answer

• 1인지 0인지 조건을 달 때는 1인 조건을 추출하는 경우라면 '!= 0' 달지말고 깔끔하게 작성하기 

def solution(n):
    return list(range(1, n+1, 2))

 

- 문제 3.

1. 문제 링크: https://school.programmers.co.kr/learn/courses/30/lessons/120818

2. 정답 코드

def solution(price):
    discount = 0
    if price >= 500000:
        discount = 20 
    elif price >= 300000:
        discount = 10
    elif price >= 100000:
        discount = 5
    return int(price * (100-discount) / 100)

def solution(price):
    discount = {500000 : 0.8, 300000 : 0.9, 100000 : 0.95, 0 : 1}
    for paid, discounted in discount.items():
        if price >= paid: 
            return int(price * discounted)

def solution(price):
    if price >= 500000:
        price *= 0.8
    elif price >= 300000:
        price *= 0.9 
    elif price >= 100000:
        price *= 0.95
    return int(price)

def solution(price):
    return int(price*0.8) if price>=500000 else int(price*0.9) if price>=300000 else int(price*0.95) if price>=100000 else int(price)

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