Cod sursa(job #305667)
Utilizator | Manea Laura Maria lama23 | Data | 18 aprilie 2009 09:39:43 |
---|---|---|---|
Problema | Fractii | Scor | 0 |
Compilator | cpp | Status | done |
Runda | Arhiva de probleme | Marime | 0.42 kb |
#include<fstream.h>
long int s,i,j,n,k,v[10001],prim[1000];
int main()
{
ifstream in("fractii.in");
ofstream out("fractii.out");
in>>n;
s=n*n;
k=1;
for(i=2;i<=n;i=i+1)
prim[i]=1;
for(i=2;i<=n;i=i+1)
if(prim[i]==1)
{for(j=i+i;j<=n;j=j+i)
prim[j]=0;
v[k]=i;
k=k+1;
}
for(i=1;i<=k-1;i=i+1)
s=s-int(n/v[i])*int(n/v[i])+int(n/v[i]);
s=s-n+1;
out<<s<<" ";
in.close();
out.close();
return 0;
}