Cod sursa(job #415027)
Utilizator | Cristi Cristi09 | Data | 10 martie 2010 20:47:58 |
---|---|---|---|
Problema | Sum | Scor | 70 |
Compilator | cpp | Status | done |
Runda | Arhiva de probleme | Marime | 0.44 kb |
#include<stdio.h>
int n,x,a,b,phi[100001];
void PHI()
{
int i,j;
for(i=1;i<=100000;++i)
phi[i]=i-1;
for(i=2;i<=100000;++i)
{
for(j=i+i;j<=100000;j+=i)
{
phi[j]-=phi[i];
}
}
}
int main()
{
FILE*f=fopen("sum.in","r");
fscanf(f,"%d",&n);
PHI();
FILE*g=fopen("sum.out","w");
for(;n;--n)
{
fscanf(f,"%d",&x);
a=phi[x];
b=phi[2*x]-a;
fprintf(g,"%d\n",2*a*x);
}
fclose(f);
fclose(g);
return 0;
}