[programmers] 문제 풀이 03

| 나이 정보가 없는 회원 수 구하기

https://school.programmers.co.kr/learn/courses/30/lessons/131528

SELECT COUNT(USER_ID)
  FROM USER_INFO
 WHERE AGE IS NULL

| 강원도에 위치한 생산공장 목록 출력하기

https://school.programmers.co.kr/learn/courses/30/lessons/131112

SELECT FACTORY_ID, FACTORY_NAME, ADDRESS
  FROM FOOD_FACTORY
 WHERE ADDRESS LIKE '강원도%'
 ORDER BY FACTORY_ID ASC;

| 몫 구하기

https://school.programmers.co.kr/learn/courses/30/lessons/120805

class Solution {
    public int solution(int num1, int num2) {
        int answer = 0;
        answer = num1 / num2;
        return answer;
    }
}

| 두 수의 곱

https://school.programmers.co.kr/learn/courses/30/lessons/120804

class Solution {
    public int solution(int num1, int num2) {
        int answer = 0;
        
        answer = num1 * num2;
        
        return answer;
    }
}

| 이름이 없는 동물의 아이디

https://school.programmers.co.kr/learn/courses/30/lessons/59039

SELECT ANIMAL_ID
  FROM ANIMAL_INS
 WHERE NAME IS NULL
 ORDER BY ANIMAL_ID;

| DATETIME에서 DATE로 형 변환

https://school.programmers.co.kr/learn/courses/30/lessons/59414

SELECT ANIMAL_ID, NAME, DATE_FORMAT(DATETIME, '%Y-%m-%d') AS 날짜
  FROM ANIMAL_INS
 ORDER BY ANIMAL_ID;

| 두 수의 나눗셈

https://school.programmers.co.kr/learn/courses/30/lessons/120806

#include <stdio.h>
#include <stdbool.h>
#include <stdlib.h>

int solution(int num1, int num2) {
    int answer = 0;
    
    answer = ((float) num1 / num2) * 1000;
    
    return answer;
}

| 각도기

https://school.programmers.co.kr/learn/courses/30/lessons/120829

class Solution {
    public int solution(int angle) {
        int answer = 0;
        
        if(0<angle && angle<90){
            answer = 1;
        }else if(angle==90){
            answer = 2;
        }else if(90<angle && angle<180){
            answer = 3;
        }else if(angle==180){
            answer = 4;
        }
        
        return answer;
    }
}

| 짝수의 합

https://school.programmers.co.kr/learn/courses/30/lessons/120831

class Solution {
    public int solution(int n) {
        int answer = 0;
        
        for(int i=1; i<=n; i++){
            if(i%2 == 0){
                answer += i;
            }
        }
        
        return answer;
    }
}

| 카테고리 별 상품 개수 구하기

https://school.programmers.co.kr/learn/courses/30/lessons/131529

SELECT SUBSTRING(PRODUCT_CODE, 1, 2) CATEGORY, COUNT(PRODUCT_CODE) PRODUCTS
  FROM PRODUCT
 GROUP BY CATEGORY
 ORDER BY PRODUCT_CODE;