[Medium] LeetCode - 122. Best Time to Buy and Sell Stock 2
문제
You are given an integer array prices where prices[i] is the price of a given stock on the ith day.
On each day, you may decide to buy and/or sell the stock. You can only hold at most one share of the stock at any time. However, you can buy it then immediately sell it on the same day.
Find and return the maximum profit you can achieve.
Example 1:
Input: prices = [7,1,5,3,6,4]
Output: 7
Explanation: Buy on day 2 (price = 1) and sell on day 3 (price = 5), profit = 5-1 = 4.
Then buy on day 4 (price = 3) and sell on day 5 (price = 6), profit = 6-3 = 3.
Total profit is 4 + 3 = 7.
Example 2:
Input: prices = [1,2,3,4,5]
Output: 4
Explanation: Buy on day 1 (price = 1) and sell on day 5 (price = 5), profit = 5-1 = 4.
Total profit is 4.
Example 3:
Input: prices = [7,6,4,3,1]
Output: 0
Explanation: There is no way to make a positive profit, so we never buy the stock to achieve the maximum profit of 0.
Constraints:
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class Solution {
public:
int maxProfit(vector<int>& prices) {
int profit = 0;
int prevPrice = prices[0];
for (int price : prices) {
if (price - prevPrice > 0) {
profit += price - prevPrice;
}
prevPrice = price;
}
return profit;
}
};
Medium 난이도길래 조금 어려울 줄 알았는데, 1분 만에 풀어버린 너무 간단한 해답이었습니다.
주식시장에서 무조건 이득을 얻는 방법은.. 상승 곡선을 그리자 마자 팔아치우면 되죠.
이전 문제로 단순하게 생각하자고 결심했던게 도움이 됐던 걸까요…! 생각보다 빠르게 효과가 찾아온듯 하네요…!?
ㅎㅎ.. 진지한 제 생각으로는 난이도 측정이 잘못된 것 같습니다. 이 문제는 Easy로 가야 맞는 것 같아요.