public class Main {
    public static void main(String[] args) {
        int[] arr = {3, 2, 7, 10, 12, 15};  
        int n = arr.length;
 
        if (n == 0) {
            System.out.println(0);
            return;
        }
 
        if (n == 1) {
            System.out.println(Math.max(0, arr[0]));
            return;
        }
 
        int[] dp = new int[n];
        dp[0] = Math.max(0, arr[0]);
        dp[1] = Math.max(dp[0], arr[1]);
 
        for (int i = 2; i < n; i++) {
            dp[i] = Math.max(dp[i - 1], arr[i] + dp[i - 2]);
        }
 
        System.out.println(dp[n - 1]);
    }
}
 

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