[프로그래머스/JAVA] 주식가격

https://programmers.co.kr/learn/courses/30/lessons/42584?language=java 

코딩테스트 연습 - 주식가격

- 이중 반복문 사용

class Solution {
    public int[] solution(int[] prices) {
        int[] answer = new int[prices.length];
        
        for(int i=0; i<prices.length; i++){
            for(int j=i+1; j<prices.length; j++){
                answer[i]++;
                if(prices[i] > prices[j]){
                    break;
                }
            }
        }
        
        return answer;
    }
}

 

- stack 사용

 

import java.util.*;

class Solution {
    public int[] solution(int[] prices) {
        int[] answer = new int[prices.length];
        Stack<Integer> stack = new Stack();
        
        for(int i=0; i<prices.length; i++){
            while(!stack.isEmpty() && prices[i] < prices[stack.peek()]){
                answer[stack.peek()] = i - stack.peek();
                stack.pop();
            }
            stack.push(i);
        }
        
        while(!stack.isEmpty()){
            answer[stack.peek()] = prices.length - stack.peek() - 1;
            stack.pop();
        }
    
        return answer;
    }
}

 

참고

https://girawhale.tistory.com/7

[프로그래머스] 주식가격(Stack) - JAVA