Cod sursa(job #274523)

Utilizator cristi_cChirac Cristian cristi_c Data 9 martie 2009 20:19:08
Problema Fractii Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.29 kb
Raporteaza aceasta sursa 
#include<fstream.h>
ifstream f("fractii.in");  
ofstream g("fractii.out");  
long long a[1000001],n,s,i,j;  
int main()
{  
f>>n;  
for(i=1;i<=n;i++)  
a[i]=i-1;  
s=0;  
for(i=1;i<=n;i++)
{  
for(j=2*i;j<=n;j=j+i)  
a[j]=a[j]-a[i];  
s=s+a[i];  
}  
g<<2*s+1;  
return 0;  
}