122. Best Time to Buy and Sell Stock II

/**
 * One Pass.
 *
 * Time Complexity: O(N)
 *
 * Space Complexity: O(1)
 *
 * N = Length of prices array.
 */
class Solution {
    public int maxProfit(int[] prices) {
        if (prices == null || prices.length <= 1) {
            return 0;
        }

        int totalProfit = 0;
        for (int i = 1; i < prices.length; i++) {
            if (prices[i - 1] < prices[i]) {
                totalProfit += prices[i] - prices[i - 1];
            }
        }

        return totalProfit;
    }
}