B. Array Walk
#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <set>
#include <queue>
#include <map>
#include <sstream>
#include <cstdio>
#include <cstring>
#include <numeric>
#include <cmath>
#include <iomanip>
#include <deque>
#include <bitset>
#include <cassert>
//#include <unordered_set>
//#include <unordered_map>
#define ll long long
#define pii pair<int, int>
#define rep(i,a,b) for(int i=a;i<=b;i++)
#define dec(i,a,b) for(int i=a;i>=b;i--)
#define forn(i, n) for(int i = 0; i < int(n); i++)
using namespace std;
int dir[4][2] = { { 1,0 },{ 0,1 } ,{ 0,-1 },{ -1,0 } };
const long long INF = 0x7f7f7f7f7f7f7f7f;
const int inf = 0x3f3f3f3f;
const double pi = acos(-1.0);
const double eps = 1e-6;
const int mod = 1e9 + 7;
inline ll read()
{
ll x = 0; bool f = true; char c = getchar();
while (c < '0' || c > '9') { if (c == '-') f = false; c = getchar(); }
while (c >= '0' && c <= '9') x = (x << 1) + (x << 3) + (c ^ 48), c = getchar();
return f ? x : -x;
}
inline ll gcd(ll m, ll n)
{
return n == 0 ? m : gcd(n, m % n);
}
void exgcd(ll A, ll B, ll& x, ll& y)
{
if (B) exgcd(B, A % B, y, x), y -= A / B * x; else x = 1, y = 0;
}
inline int qpow(int x, ll n) {
int r = 1;
while (n > 0) {
if (n & 1) r = 1ll * r * x % mod;
n >>= 1; x = 1ll * x * x % mod;
}
return r;
}
inline int inv(int x) {
return qpow(x, mod - 2);
}
ll lcm(ll a, ll b)
{
return a * b / gcd(a, b);
}
/**********************************************************/
const int N = 5e3 + 5;
int main() {
ios::sync_with_stdio(false);cin.tie(nullptr);
int T;
cin >> T;
while (T--)
{
int n, k, z;
cin >> n >> k >> z;
vector<int> a(n + 1);
rep(i, 1, n)
cin >> a[i];
int pre = 0, mx = 0, res = 0;
k++;
rep(i, 1, k)
{
pre += a[i];
if(i<n)
mx = max(a[i] + a[i + 1], mx);
res = max(res, mx * min((k - i) / 2, z) + pre);
}
cout << res << endl;
}
}