1 #include<bits/stdc++.h> 2 using namespace std; 3 typedef long long ll; 4 int main(){ 5     ll n,k; 6     cin>>n>>k; 7     ll ans=n/k; 8     if(ans%2==1){ 9         cout<<"YES";10     }11     else cout<<"NO";12 }

 1 #include<bits/stdc++.h> 2 using namespace std; 3 typedef long long ll; 4 bool zi[26]; 5 int main(){ 6     string s,t,tt; 7     cin>>s>>t; 8     for(int i=0;i<s.size();i++){ 9         zi[s[i]-‘a‘]=true;10     }11     int n;12     cin>>n;13     for(int i=0;i<n;i++){14         cin>>tt;15         int aa=0,kk;16         bool f1=true;17         18         for(int j=0;j<t.size();j++){19             kk=j+aa;20             if(t[j]!=‘?‘&&t[j]!=‘*‘&&t[j]!=tt[kk]){21                 cout<<"NO\n";22                 f1=false;23                 break;24             }25             26             if(t[j]==‘?‘){27                 bool flag=false;28                 if(zi[tt[kk]-‘a‘]) flag=true;29                 if(flag) continue;30                 else{31                     cout<<"NO\n";32                     f1=false;33                     break;34                 }35             }36             if(t[j]==‘*‘){37                 int len=tt.size()-t.size();38                 if(len<-1){39                     cout<<"NO\n";40                     f1=false;41                     break;42                 }43                 if(len==-1){44                     aa--;45                     continue;46                 }47                 bool flag=false;48                 for(int k=0;k<=len;k++){49                     if(zi[tt[k+kk]-‘a‘]){ flag=true;break;} 50                 }51                 if(flag){52                     cout<<"NO\n";53                     f1=false;54                     break;55                 }56                 else{57                     aa+=len;58                     continue;59                 }60             }61             if(j==t.size()-1&&kk!=tt.size()-1){62                 cout<<"NO\n";63                 f1=false;64                 break;65             }66         }67         if(f1) cout<<"YES\n";68     }69 }

 1 #include<bits/stdc++.h> 2 #define maxv 100005 3 using namespace std; 4 typedef long long ll; 5 vector<int>G[maxv]; 6 int root; 7 int parent[20][maxv]; 8 int depth[maxv]; 9 int a,b,c;10 int n,q,t;11 void dfs(int v,int p,int d){12     parent[0][v]=p;13     depth[v]=d;14     for(int i=0;i<G[v].size();i++){15         if(G[v][i]!=p) dfs(G[v][i],v,d+1);16     }17 }18 19 void init(){20     dfs(0,-1,0);21     for(int k=0;k+1<20;k++){22         for(int v=0;v<n;v++){23             if(parent[k][v]<0) parent[k+1][v]=-1;24             else parent[k+1][v]=parent[k][parent[k][v]];25         }26     }27 }28 29 int lca(int u,int v){30     if(depth[u]>depth[v]) swap(u,v);31     for(int k=0;k<20;k++){32         if((depth[u]-depth[v])>>k&1){33             v=parent[k][v];34         }35     }36     if(u==v) return u;37     for(int k=20-1;k>=0;k--){38         if(parent[k][u]!=parent[k][v]){39             u=parent[k][u];40             v=parent[k][v];41         }42     }43     return parent[0][u];44 }45 int dis(int a,int b,int u){46     return depth[a]+depth[b]-2*depth[u];47 } 48 int main(){49     cin>>n>>q;50     for(int i=0;i<n-1;i++){51          cin>>t;52          G[i+1].push_back(t-1);53          G[t-1].push_back(i+1);54     }55     init();56     for(int j=0;j<q;j++){57         cin>>a>>b>>c;58         a-=1;59         b-=1;60         c-=1;61         int v1,v2,v3;62         v1=lca(a,b);63         v2=lca(b,c);64         v3=lca(c,a);65         int ab,bc,ac;66         ab=dis(a,b,v1);67         bc=dis(b,c,v2);68         ac=dis(a,c,v3);69         int ans=max(max(ab+bc-ac,bc+ac-ab),ac+ab-bc)/2+1;70         printf("%d\n",ans);71     }72     return 0;73 }