#include <bits/stdc++.h>
using namespace std;
#include "peru.h"
#define ll long long
const ll p = 1e9+7;
int solve(int n, int k, int* v){
vector<ll> dp(n); // min effort, last idx of prev segment
function<ll(int)> get = [&](int idx) {
if (idx < 0) return 0ll;
return dp[idx];
};
// vector<int> mon_s;
int last_opt_idx = -1; // points to last!!! idx such that v[i] is NOT active
multiset<int> active;
for (int i = 0; i < n; i++) {
// while (!mon_s.empty() && v[mon_s.back()] <= v[i]) mon_s.pop_back();
// mon_s.push_back(i);
// if (i-k >= 0) active.erase(active.find(v[i-k]));
active.insert(v[i]);
// last_opt_idx = max(last_opt_idx, i-k);
if (last_opt_idx < i-k) {
last_opt_idx++;
active.erase(active.find(v[last_opt_idx]));
assert(last_opt_idx == i-k);
}
auto do_increment = [&]() {
if (last_opt_idx == i-1) return false;
int curr_val = get(last_opt_idx) + (*active.rbegin());
last_opt_idx++;
active.erase(active.find(v[last_opt_idx]));
int next_val = get(last_opt_idx) + (*active.rbegin());
active.insert(v[last_opt_idx]);
last_opt_idx--;
return next_val <= curr_val;
};
while (do_increment()) {
last_opt_idx++;
active.erase(active.find(v[last_opt_idx]));
}
ll val = get(last_opt_idx) + (*active.rbegin());
// pair<ll, int> curmin = {1e18, 0};
// int runmax = v[i];
// for (int j = i-1; j >= i-k; j--) {
// curmin = min(curmin, {(ll)get(j).first + (ll)runmax, j});
// if (j < 0) break;
// runmax = max(runmax, v[j]);
// }
dp[i] = val;
}
ll factor = 1;
ll res = 0;
for (int i = n-1; i >= 0; i--) {
res += ((dp[i]%p)*factor) % p;
res %= p;
factor *= 23;
factor %= p;
}
return res;
}
