For Me

https://school.programmers.co.kr/learn/courses/30/lessons/12948

public class Solution {
    public string solution(string phone_number) {
        string answer = "";
        
        string temp = phone_number.Substring(phone_number.Length -4,4);
        for(int i = 0; i < phone_number.Length - 4; ++i)
        {
            answer += "*";
        }
        answer += temp;
        return answer;
    }
}

https://school.programmers.co.kr/learn/courses/30/lessons/12931

using System;

public class Solution {
    public int solution(int n) {
        int answer = 0;
        while(n>0){
           answer += n % 10;
           n = n / 10;
        }
        return answer;
    }
}

https://school.programmers.co.kr/learn/courses/30/lessons/12954

public class Solution {
    public long[] solution(int x, int n) {
        long[] answer = new long[n];
        for (int i=0; i<n; i++)
        {
            answer[i] = (long)x * (i + 1);
        }
        return answer;
    }
}

https://school.programmers.co.kr/learn/courses/30/lessons/12937

public class Solution {
    public string solution(int num) {
        string answer = "";
        
        if (num % 2 == 0) answer = "Even"; else answer = "Odd";
        
        return answer;
    }
}

https://school.programmers.co.kr/learn/courses/30/lessons/120853

using System;

public class Solution {
    public int solution(string s) {
        int answer = 0;
        
            string[] temp = s.Split(" ");
            for (int i=0; i < temp.Length; i++)
            { 
                if (temp[i] != "Z" )
                {
                  answer += int.Parse(temp[i]);
                }
                else
                {
                    answer -= int.Parse(temp[i-1]);
                }
            }
        return answer;
    }
}

https://school.programmers.co.kr/learn/courses/30/lessons/59408

SELECT COUNT(DISTINCT NAME) AS "COUNT"
FROM ANIMAL_INS
;

https://school.programmers.co.kr/learn/courses/30/lessons/59038?language=oracle 

SELECT MIN(DATETIME) AS "시간"
FROM ANIMAL_INS
;

https://school.programmers.co.kr/learn/courses/30/lessons/59406

SELECT COUNT(ANIMAL_TYPE) AS COUNT
FROM ANIMAL_INS;