#include <iostream>
#include <bits/stdc++.h>
using namespace std;
int f[1000005];
int MaximumNonAdj(std::vector<int> arr)
{
    int Max=*max_element(arr.begin(), arr.end());
    if(arr.size()==1)return arr[0];
    memset(f, 0, sizeof(f));
    f[0]=arr[0];
    f[1]=max(f[0], arr[1]);
    for(int i=2;i<arr.size();i++)
    {
        f[i]=max(max(f[i-2]+arr[i], f[i-1]), f[i-2]);
    }
    return max(Max,*max_element(f, f+arr.size()));
}
int main() {
	vector<int> arr;
	int n; 
	for(int j=0;j<6;j++)
	{
		cin>>n;
		arr.resize(n);
		for(int i=0;i<n;i++)cin>>arr[i];
		cout<<MaximumNonAdj(arr)<<endl;
	}
	return 0;
}

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5 
161 -75 -54 163 -63 
4
121 -63 -110 86
3
-104 46 79 
5 
69 2 -92 69 102 
2 
-32 157 
4 
96 196 57 150