#include<bits/stdc++.h> using namespace std; inline int mo(int n) { if(n==4) return cout<<"4,5-->9,10\n8,9-->4,5\n2,3-->8,9\n7,8-->2,3\n1,2-->7,8\n",0; cout<<n<<","<<n+1<<"-->"<<2*n+1<<","<<2*n+2<<endl; cout<<2*n-1<<","<<2*n<<"-->"<<n<<","<<n+1<<endl; return mo(n-1); } signed main() { int n; cin>>n; mo(n); return 0; }