View Code of Problem 3942

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pdd;

#define INF 0x7f7f7f
#define mem(a, b) memset(a , b , sizeof(a))
#define FOR(i, x, n) for(int i = x;i <= n; i++)

// const ll mod = 998244353;
// const ll P = 1e9 + 7;
// const int maxn = 1e5 + 10;
// const double eps = 1e-6;

ll n, x;

const int N = 3e5 + 10;

ll f[N][3][3];

ll a[N];

void solve() {
    cin >> n >> x;
    for(int i = 1;i <= n; i++) cin >> a[i];

    mem(f, -1);
    f[0][0][0] = 0;

    for(int i = 0;i <= n; i++) {
        for(int j = 0;j < 3; j++) {
            for(int k = 0;k < 3; k++) {
                if(j >= 1)
                    f[i][j][k] = max(f[i][j][k], f[i][j - 1][k]);
                if(k >= 1)
                    f[i][j][k] = max(f[i][j][k], f[i][j][k - 1]);
                if(i >= 1)
                f[i][j][k] = max(f[i][j][k], f[i - 1][j][k] + (j == 1 ? a[i] : 0) * (k == 1 ? x : 1));
            }
        }
    }
    cout << f[n][2][2] << endl;
}

signed main() {
    ios_base::sync_with_stdio(false);
    //cin.tie(nullptr);
    //cout.tie(nullptr);
#ifdef FZT_ACM_LOCAL
    freopen("in.txt", "r", stdin);
    freopen("out.txt", "w", stdout);
    signed test_index_for_debug = 1;
    char acm_local_for_debug = 0;
    do {
        if (acm_local_for_debug == '$') exit(0);
        if (test_index_for_debug > 20)
            throw runtime_error("Check the stdin!!!");
        auto start_clock_for_debug = clock();
        solve();
        auto end_clock_for_debug = clock();
        cout << "Test " << test_index_for_debug << " successful" << endl;
        cerr << "Test " << test_index_for_debug++ << " Run Time: "
             << double(end_clock_for_debug - start_clock_for_debug) / CLOCKS_PER_SEC << "s" << endl;
        cout << "--------------------------------------------------" << endl;
    } while (cin >> acm_local_for_debug && cin.putback(acm_local_for_debug));
#else
    solve();
#endif
    return 0;
}