Cod sursa(job #3254432)

Utilizator Silviu643Dumitrescu Silviu Florian Silviu643 Data 7 noiembrie 2024 16:36:59
Problema Iepuri Scor 0
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 0.74 kb
#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("inel.in");
ofstream fout("inel.out");
int n,x[20],nr,f[20];
bool prim(int x)
{
    if(x==1 || x==0) return 0;
    if(x==2 || x==3) return 1;
    for(int i=2;i*i<=x;i++) if(x%i==0) return 0;
    return 2;
}
bool verif(int k)
{
    if(prim(x[k]+x[k-1])) return 1;
    return 0;
}
void bkt(int k)
{
    for(int i=2;i<=n;i++)
    {
        x[k]=i;
        if(k<=n && verif(k) && !f[i])
        {
            if(k==n) nr++;
            else
            {
                f[i]=1;
                bkt(k+1);
            }
            f[i]=0;
        }
    }
}
int main()
{
    fin>>n;
    bkt(2);
    x[1]=1;
    f[1]=1;
    fout<<nr;
    return 0;
}