写法1:

#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;

const int N = 1e5 + 10;

int t, n;
int w[N], f[N];

int main()
{
    cin >> t;
    while(t --)
    {
        cin >> n;
        for (int i = 0; i < n; i ++)
            cin >> w[i];

        memset(f, 0, sizeof f);
        f[0] = w[0];
        f[1] = max(w[0], w[1]);
        for (int i = 2; i < n; i ++)
            f[i] = max(f[i - 1], f[i - 2] + w[i]);
        cout << f[n - 1] << endl;
    }
    return 0;
}

写法2:

#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;

const int N = 1e5 + 10;

int t;
int f[N];

int main()
{
    cin >> t;
    while(t --)
    {
        int n, w;
        cin >> n;

        memset(f, 0, sizeof f);

        cin >> w;
        f[1] = w;
        for (int i = 2; i <= n; i ++)
        {
            cin >> w;
            f[i] = max(f[i - 1], f[i - 2] + w);
        }

        cout << f[n] << endl;
    }
    return 0;
}