import java.lang.*;
import java.io.*;

class GFG {
	public static void main (String[] args) {
		//code
		Scanner sc = new Scanner(System.in);
		int T = sc.nextInt();
		while(T--> 0)
		{
		    int n = sc.nextInt();
		    int arr[] = new int[n];
		    for(int i = 0; i < n; i++){
		        arr[i] = sc.nextInt();
		        
		    }
		    if(n == 1)
		      {
		          System.out.println(arr[0]);
		          continue;
		      }
		    System.out.println(findMaxSum(arr, n));
		    
		}
	}
	
	static int findMaxSum(int arr[], int n){
	    
	    int dp[] = new int[n];
	    dp[0] = arr[0];
	    dp[1] = Math.max(dp[0], arr[1]);
	    
	    for(int i = 2; i < n ; i++){
	        dp[i] = Math.max(dp[i - 2] + arr[i], Math.max(dp[i - 1], arr[i]));
	        
	    }
	    
	    
	    return dp[n - 1];
	}
}
