/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		int[] a = {2,4,6,7,8};
		int k = 5;
		int[] dp = new int[k];
 
		//  dp[0] can be a[0] or 0 
		dp[0] = Math.max(a[0],0);
 
		// dp[1] has 2 poss 1) if we dont pick a[1] than best possible soltuion is dp[0]
		//  if we pick it than we can't take dp[0]
		dp[1] = Math.max(dp[0],a[1]);
 
		for(int i = 2; i < k; i++){
			dp[i] = Math.max(dp[i-1],a[i] + dp[i-2]);
		}
 
		System.out.print(dp[k-1]);
 
	}
}

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