Cod sursa(job #109354)

Utilizator mihai0110Bivol Mihai mihai0110 Data 25 noiembrie 2007 10:24:53
Problema Pairs Scor 20
Compilator cpp Status done
Runda preONI 2008, Runda 1, Clasa a 10-a Marime 0.39 kb
#include<stdio.h>
FILE *f=fopen("pairs.in","r");
FILE *g=fopen("pairs.out","w");
long i,j,n,nr=0,a[100001];
long gcd(long a,long b)
{
if(b==0)
return a;
else
return gcd(b, a%b);
}
int main(void)
{
fscanf(f,"%ld",&n);
for(i=1;i<=n;i++)
fscanf(f,"%ld",&a[i]);
for(i=1;i<n;i++)
for(j=i+1;j<=n;j++)
if(gcd(a[i],a[j])==1)
nr++;
fprintf(g,"%ld",nr);
fclose(f);
fclose(g);
return 0;
}