Cod sursa(job #566075)

Utilizator bam67Blidar Adrian Marian bam67 Data 28 martie 2011 17:11:06
Problema Fractii Scor 30
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.29 kb
Raporteaza aceasta sursa 
#include<fstream.h>
long s[1000009],sum=0,i,j,n;
int main()
{ifstream f("fractii.in");
ofstream h("fractii.out");
f>>n;
for(i=1;i<=n;i++)
s[i]=i-1;
for(i=2;i<=n;i++)
for(j=i+i;j<=n;j+=i)
if(j%i==0) s[j]=s[j]-s[i];

for(i=1;i<=n;i++)
sum=sum+s[i];
sum=2*sum+1;
h<<sum;
return 0;}