Cod sursa(job #216502)

Utilizator SheepBOYFelix Liviu SheepBOY Data 24 octombrie 2008 19:01:29
Problema Sum Scor 0
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.37 kb
#include<stdio.h>
int e[100000];
void euler()
{
	int i;
	for(i=0;i<100000;i++)
		e[i]=i;
	for(i=2;i<100000;i++)
	{
		if(e[i]==i)
			e[i]--;
	for(int j=i+i;j<100000;j++)	
		e[j]=e[j]/i*(i-1);
	}
}
int main()
{
	int x,n;
	freopen("sum.in","r",stdin);
	freopen("sum.out","w",stdout);
	scanf("%d%d",&n,&x);
	euler();
	printf("%d",2*e[x]*x);	
	return 0;
}