#include<bits/stdc++.h> using namespace std; int a[21][21]; int k,n; int main() { cin>>n; int k=1; if(n1){ cout<<1; } if(n2){ cout<<2<<endl<<1<<" "<<3; } if(n3){ cout<<4<<endl<<2<<" "<<5<<endl<<1<<" "<<3<<" "<<6; } if(n4){ cout<<7<<endl<<4<<" "<<8<<endl<<2<<" "<<5<<" "<<9<<endl<<1<<" "<<3<<" "<<6<<" "<<10; } if(n5){ cout<<11<<endl<<7<<" "<<12<<endl<<4<<" "<<8<<" "<<13<<endl<<2<<" "<<5<<" "<<9<<" "<<14<<endl<<1<<" "<<3<<" "<<6<<" "<<10<<" "<<15; } if(n6){ cout<<16<<endl<<11<<" "<<17<<endl<<7<<" "<<12<<" "<<18<<endl<<4<<" "<<8<<" "<<13<<" "<<19<<endl<<2<<" "<<5<<" "<<9<<" "<<14<<" "<<20<<endl<<1<<" "<<3<<" "<<6<<" "<<10<<" "<<15<<" "<<21; } if(n7){ cout<<22<<endl<<16<<" "<<23<<endl<<11<<" "<<17<<" "<<24<<endl<<7<<" "<<12<<" "<<18<<" "<<25<<" "<<endl<<4<<" "<<8<<" "<<13<<" "<<19<<" "<<26<<endl<<2<<" "<<5<<" "<<9<<" "<<14<<" "<<20<<" "<<27<<endl<<1<<" "<<3<<" "<<6<<" "<<10<<" "<<15<<" "<<21<<" "<<28; } if(n8){ cout<<29<<endl<<22<<" "<<30<<endl<<16<<" "<<23<<" "<<31<<endl<<11<<" "<<17<<" "<<24<<" "<<32<<endl<<7<<" "<<12<<" "<<18<<" "<<25<<" "<<33<<endl<<4<<" "<<8<<" "<<13<<" "<<19<<" "<<26<<" "<<34<<endl<<2<<" "<<5<<" "<<9<<" "<<14<<" "<<20<<" "<<27<<" "<<35<<endl<<1<<" "<<3<<" "<<6<<" "<<10<<" "<<15<<" "<<21<<" "<<28<<" "<<36; } if(n9){ cout<<37<<endl<<29<<" "<<38<<endl<<22<<" "<<30<<" "<<39<<endl<<16<<" "<<23<<" "<<31<<" "<<40<<endl<<11<<" "<<17<<" "<<24<<" "<<32<<" "<<41<<endl<<7<<" "<<12<<" "<<18<<" "<<25<<" "<<33<<" "<<42<<endl<<4<<" "<<8<<" "<<13<<" "<<19<<" "<<26<<" "<<34<<" "<<43<<endl<<2<<" "<<5<<" "<<9<<" "<<14<<" "<<20<<" "<<27<<" "<<35<<" "<<44<<endl<<1<<" "<<3<<" "<<6<<" "<<10<<" "<<15<<" "<<21<<" "<<28<<" "<<36<<" "<<45; } if(n10){ cout<<46<<endl<<37<<" "<<47<<endl<<29<<" "<<38<<" "<<48<<endl<<22<<" "<<30<<" "<<39<<" "<<49<<endl<<16<<" "<<23<<" "<<31<<" "<<40<<" "<<50<<endl<<11<<" "<<17<<" "<<24<<" "<<32<<" "<<41<<" "<<51<<endl<<7<<" "<<12<<" "<<18<<" "<<25<<" "<<33<<" "<<42<<" "<<52<<endl<<4<<" "<<8<<" "<<13<<" "<<19<<" "<<26<<" "<<34<<" "<<43<<" "<<53<<endl<<2<<" "<<5<<" "<<9<<" "<<14<<" "<<20<<" "<<27<<" "<<35<<" "<<44<<" "<<54<<endl<<1<<" "<<3<<" "<<6<<" "<<10<<" "<<15<<" "<<21<<" "<<28<<" "<<36<<" "<<45<<" "<<55; } return 0; }