Cod sursa(job #46294)
Utilizator | Data | 2 aprilie 2007 15:01:08 | |
---|---|---|---|
Problema | 12-Perm | Scor | 5 |
Compilator | cpp | Status | done |
Runda | Arhiva de probleme | Marime | 0.25 kb |
#include<fstream.h>
ifstream f("12perm.in");
ofstream g("12perm.out");
long i,n,a[1500000];
int main()
{
f>>n;
a[1]=1;
a[2]=2;
a[3]=6;
a[4]=12;
for(i=5;i<=n;i++)
a[i]=a[i-1]+a[i-3]+2*(i-2);
g<<a[n];
f.close();
g.close();
return 0;
}