Cod sursa(job #4860)

Utilizator crawlerPuni Andrei Paul crawler Data 8 ianuarie 2007 14:43:54
Problema 12-Perm Scor 0
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.34 kb
Raporteaza aceasta sursa 
#include <stdio.h>

int main()
{
  register long n, v[16],mod=1<<20-1,i;
  
  freopen("12perm.in","r",stdin);
  freopen("12perm.out","w",stdout);

  scanf("%ld",&n);


  v[1]=1;
  v[2]=2;
  v[3]=6;
  v[4]=12;
  
  for(i=4;i<=n;++i)
   v[i&15]=(v[(i-1)&15]+v[i-3]+(i-2)<<1)&mod;

  printf("%ld",v[n&15]);


  return 0;
}