Untitled

public class CurrencyTradingOptimization {
    public static int optimizedSolution(int[] rates, int[] strategy, int k) {
        int n = strategy.length;

        // Initial profit calculation
        int initialProfit = 0;
        for (int i = 0; i < n; i++) {
            if (strategy[i] == -1) {
                initialProfit -= rates[i]; // Buying, subtract the rate
            } else if (strategy[i] == 1) {
                initialProfit += rates[i]; // Selling, add the rate
            }
        }

        int maxProfit = initialProfit;
        int currentProfit = initialProfit;

        // Iterate through all possible ranges of length k
        for (int i = 0; i <= n - k; i++) {
            // Backup original values in the range
            int[] originalValues = new int[k];
            System.arraycopy(strategy, i, originalValues, 0, k);

            // Calculate the profit change when modifying the current range
            int profitChange = 0;

            // Remove the effect of original values in the first half
            for (int j = 0; j < k / 2; j++) {
                if (originalValues[j] == -1) {
                    profitChange += rates[i + j]; // Undo buying, add back the rate
                } else if (originalValues[j] == 1) {
                    profitChange -= rates[i + j]; // Undo selling, subtract the rate
                }
            }

            // Remove the effect of original values in the second half
            for (int j = k / 2; j < k; j++) {
                if (originalValues[j] == -1) {
                    profitChange += rates[i + j]; // Undo buying, add back the rate
                } else if (originalValues[j] == 1) {
                    profitChange -= rates[i + j]; // Undo selling, subtract the rate
                }
            }

            // Add the effect of new values (setting to 1) in the second half
            for (int j = k / 2; j < k; j++) {
                profitChange += rates[i + j]; // Selling, add the rate
            }

            // Update the current profit based on the change
            currentProfit = initialProfit + profitChange;
            maxProfit = Math.max(maxProfit, currentProfit);
        }

        return maxProfit;
    }

    public static void main(String[] args) {
        int[] rates = {2, 4, 1, 5, 10, 6};
        int[] strategy = {-1, 1, 0, 1, -1, 0};
        int k = 4;

        // Run the optimized solution function on the provided test case
        int result = optimizedSolution(rates, strategy, k);
        System.out.println(result); // Expected output: 18
    }
}