Best Time to Buy and Sell Stock
Description
You are given an array prices
where prices[i]
is the price of a given stock on the ith
day.
You want to maximize your profit by choosing a single day to buy one stock and choosing a different day in the future to sell that stock.
Return the maximum profit you can achieve from this transaction. If you cannot achieve any profit, return 0
.
Example 1:
Input: prices = [7,1,5,3,6,4] Output: 5 Explanation: Buy on day 2 (price = 1) and sell on day 5 (price = 6), profit = 6-1 = 5. Note that buying on day 2 and selling on day 1 is not allowed because you must buy before you sell.
Example 2:
Input: prices = [7,6,4,3,1] Output: 0 Explanation: In this case, no transactions are done and the max profit = 0.
Constraints:
1 <= prices.length <= 105
0 <= prices[i] <= 104
Solution(javascript)
/**
* @param {number[]} prices
* @return {number}
*/
var maxProfit = function(prices) {
let buy;
let profit = 0;
for(let i = 0; i < prices.length; i++) {
if (i == 0 || prices[i] < buy) {
buy = prices[i];
} else if (prices[i] > buy && profit < prices[i] - buy) {
profit = prices[i] - buy
}
}
return profit;
};