#include #define rep(i,n) for(int i = 0; i < (n); ++i) #define drep(i,n) for(int i = (n)-1; i >= 0; --i) #define srep(i,s,t) for (int i = s; i < t; ++i) using namespace std; typedef long long int ll; typedef pair P; #define yn {puts("Yes");}else{puts("No");} struct edge{ int to, cost; }; const int INF = 1001001001; const int MAX_N = 200005; const int MAX_V = 200005; vector G[MAX_V]; int d[MAX_V]; void dijkstra(int s){ // greater

を指定することでfirstが小さい順に取り出せるようにする priority_queue, greater

> que; fill(d, d+MAX_V, INF); d[s] = 0; que.push(P(0, s)); while(!que.empty()){ P p = que.top(); que.pop(); int v = p.second; if(p.first > d[v]) continue; for(int i=0; i d[v] + e.cost){ d[e.to] = d[v] + e.cost; que.push(P(d[e.to], e.to)); } } } } int main() { int n, k; cin >> n >> k; srep(i,1,n){ edge e; e.to = i + 3; e.cost = 1; if(e.to <= n) G[i].push_back(e); e.to = i * 2; if(e.to <= n) G[i].push_back(e); } dijkstra(1); if(d[n] <= k) yn; return 0; }