BestTimeToBuyAndSellStocksII.java

// Optimised Solution TC: O(n) SC: O(1)
/*
Runtime: 1 ms, faster than 97.51% of Java online submissions for Best Time to Buy and Sell Stock II.
Memory Usage: 44.5 MB, less than 39.82% of Java online submissions for Best Time to Buy and Sell Stock II.
*/
class Solution {
    public int maxProfit(int[] prices) {
        int maxprofit = 0;
        for (int i = 1; i < prices.length; i++) {
            if (prices[i] > prices[i - 1])
                maxprofit += prices[i] - prices[i - 1];
        }
        return maxprofit;
    }
}


// Brute Force Solution TC: O(n) SC: O(1)
class Solution {
    public int maxProfit(int[] a){
        
        int min = a[0];
        int sum = 0;
        int profit = 0;
        int diff = 0;
        
        for(int i=1; i<a.length; i++){
            if(min > a[i]){
                min = a[i];
            }
            diff = a[i] - min;
            
            if(sum < diff){
                sum = diff;
                min = a[i];
                // profit = profit + diff;
            }
            profit = profit + sum;
            sum=0;
            
        }
        
        return profit;

    }
}