122.go

package easy_collection

/**
 * 122. Best Time to Buy and Sell Stock II
 * <p>
 * Say you have an array for which the ith element is the price of a given stock on day i.
 * <p>
 * Design an algorithm to find the maximum profit. You may complete as many transactions as you like (i.e., buy one and sell one share of the stock multiple times).
 * <p>
 * Note: You may not engage in multiple transactions at the same time (i.e., you must sell the stock before you buy again).
 * <p>
 * Example 1:
 * <p>
 * Input: [7,1,5,3,6,4]
 * Output: 7
 * <p>
 * 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.
 * <p>
 * Example 2:
 * <p>
 * Input: [1,2,3,4,5]
 * Output: 4
 * <p>
 * Explanation: Buy on day 1 (price = 1) and sell on day 5 (price = 5), profit = 5-1 = 4.
 * Note that you cannot buy on day 1, buy on day 2 and sell them later, as you are
 * engaging multiple transactions at the same time. You must sell before buying again.
 * <p>
 * Example 3:
 * <p>
 * Input: [7,6,4,3,1]
 * Output: 0
 * <p>
 * Explanation: In this case, no transaction is done, i.e. max profit = 0.
 */

func maxProfit122(prices []int) int {
	target := 0
	for i, p := range prices {
		if i > 0 {
			if p > prices[i-1] {
				target += p - prices[i-1]
			}
		}
	}
	return target
}