#include using namespace std; #include using namespace atcoder; using ll = long long; #define rep(i, n) for (ll i = 0; i < ll(n); i++) int main(){ int n,m,l; cin >> n >> m >> l; vector a(n); rep(i,n) cin >> a[i]; vector seen(1001); priority_queue,vector>,greater>> pq; pq.emplace(0,l); seen[l] = 1; while(!pq.empty()){ auto [v,col] = pq.top(); pq.pop(); for(int i = v+1;i < n;i++){ int nxt = (col+a[i])/2; if(seen[nxt]) continue; seen[nxt] = 1; pq.emplace(i,nxt); } } if(seen[m]) cout << "Yes" << endl; else cout << "No" << endl; }