Cod sursa(job #415038)

Utilizator Cristi09Cristi Cristi09 Data 10 martie 2010 20:53:13
Problema Sum Scor 0
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.43 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];
		fprintf(g,"%lld\n",2*a*x);
	}
	fclose(f);
	fclose(g);
	return 0;
}