Cod sursa(job #109537)

Utilizator ViksenVictor-Nicolae Savu Viksen Data 25 noiembrie 2007 11:38:55
Problema Pairs Scor 20
Compilator cpp Status done
Runda preONI 2008, Runda 1, Clasele 11-12 Marime 0.55 kb
#include <stdio.h>

int A[100000];

int main ()
{
    int n,i,j,s=0,x,y;
    freopen ( "pairs.in" , "r" , stdin );
    scanf ( "%d" , &n );
    for ( i=0 ; i<n ; i++ )
        scanf ( "%d" , &A[i] );
    fclose ( stdin );

    for ( i=0 ; i<n ; i++ )
        for ( j=i+1 ; j<n ; j++ ) {
            for ( x=A[i],y=A[j] ; x && y ; )
                if (x>y) x%=y; else y%=x;
            if (x) s+=(x==1); else s+=(y==1);
        }

    freopen ( "pairs.out" , "w" , stdout );
    printf ( "%d\n" , s );
    fclose ( stdout );

    return 0;
}