#include using namespace std; #define SZ(x) (int) (x).size() #define REP(i, n) for(int i = 0; i < (n); i++) #define FOR(i, a, b) for(int i = (a); i < (b); i++) #define REPR(i, n) for(int i = (n) -1; i >= 0; i--) #define ALL(s) (s).begin(), (s).end() #define so(V) sort(ALL(V)) #define rev(V) reverse(ALL(V)) #define uni(v) v.erase(unique(ALL(v)), (v).end()) typedef long long unsigned int llu; typedef long long ll; typedef vector vi; typedef vector vll; typedef vector vb; typedef vector vvi; const double EPS = 1e-9; const int MOD = 1e9 + 7; const int INF = (1 << 29); const ll LINF = 1e18; const double PI = acos(-1); template vector make_v(size_t a) { return vector(a); } template auto make_v(size_t a, Ts... ts) { return vector(ts...))>( a, make_v(ts...)); } template typename enable_if::value == 0>::type fill_v( T& t, const V& v) { t = v; } template typename enable_if::value != 0>::type fill_v( T& t, const V& v) { for(auto& e: t) fill_v(e, v); } template bool chmax(T& a, const T& b) { if(a < b) { a = b; return true; } return false; } template bool chmin(T& a, const T& b) { if(a > b) { a = b; return true; } return false; } template istream& operator>>(istream& is, pair& p) { cin >> p.first >> p.second; return is; } template istream& operator>>(istream& is, vector& vec) { for(T& x: vec) is >> x; return is; } template ostream& operator<<(ostream& os, vector& vec) { REP(i, SZ(vec)) { if(i != 0) os << " "; os << vec[i]; } return os; } int main() { cin.tie(nullptr); ios::sync_with_stdio(false); ll N, X, M; cin >> N >> X >> M; vll A(N); cin >> A; ll cur = 1; REPR(i, N) { while(M >= 0 && A[i] / cur >= X) { cur *= 2; M -= i + 1; } if(M < 0) { cout << "No" << endl; return 0; } } cout << "Yes" << endl; return 0; }