#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include template inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; } template inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; } const long long MAX = 5100000; const long long INF = 1LL << 60; const long long mod = 1000000007LL; //const long long mod = 998244353LL; using namespace std; typedef unsigned long long ull; typedef long long ll; struct mint { ll x; // typedef long long ll; mint(ll x = 0) :x((x% mod + mod) % mod) {} mint& operator+=(const mint a) { if ((x += a.x) >= mod) x -= mod; return *this; } mint& operator-=(const mint a) { if ((x += mod - a.x) >= mod) x -= mod; return *this; } mint& operator*=(const mint a) { (x *= a.x) %= mod; return *this; } mint operator+(const mint a) const { mint res(*this); return res += a; } mint operator-(const mint a) const { mint res(*this); return res -= a; } mint operator*(const mint a) const { mint res(*this); return res *= a; } mint pow(ll t) const { if (!t) return 1; mint a = pow(t >> 1); a *= a; if (t & 1) a *= *this; return a; } // for prime mod mint inv() const { return pow(mod - 2); } mint& operator/=(const mint a) { return (*this) *= a.inv(); } mint operator/(const mint a) const { mint res(*this); return res /= a; } }; struct Matrix { vector > val; Matrix(int n, int m, long long x = 0) : val(n, vector(m, x)) {} void init(int n, int m, long long x = 0) { val.assign(n, vector(m, x)); } size_t size() const { return val.size(); } inline vector& operator [] (int i) { return val[i]; } }; Matrix operator * (Matrix A, Matrix B) { Matrix R(A.size(), B[0].size()); for (int i = 0; i < A.size(); ++i) for (int j = 0; j < B[0].size(); ++j) for (int k = 0; k < B.size(); ++k) R[i][j] = (R[i][j] + A[i][k] * B[k][j] % mod) % mod; return R; } Matrix modpow(Matrix A, long long n) { Matrix R(A.size(), A.size()); for (int i = 0; i < A.size(); ++i) R[i][i] = 1; while (n > 0) { if (n & 1) R = R * A; A = A * A; n >>= 1; } return R; } int main() { /* cin.tie(nullptr); ios::sync_with_stdio(false); */ ll N, M, K, p, q; cin >> N >> M >> K >> p >> q; mint pr1 = mint(p) * mint(q).inv(); mint pr2 = mint(1) - pr1; Matrix mat(2, 2); mat[0][0] = pr2.x; mat[0][1] = pr1.x; mat[1][0] = pr1.x; mat[1][1] = pr2.x; Matrix ini1(2, 1), ini2(2, 1); ini1[0][0] = 1; ini2[1][0] = 1; Matrix res1 = modpow(mat, K) * ini1; Matrix res2 = modpow(mat, K) * ini2; vector b(N); for (ll i = 0; i < N; i++) scanf("%lld", &b[i]); mint res = 0; for (ll i = 0; i < M; i++) { res += mint(b[i]) * res1[0][0]; } for (ll i = M; i < N; i++) { res += mint(b[i]) * res2[0][0]; } cout << res.x << endl; return 0; }