#include<stdio.h>
int main()
{
long m[100000],n,x,y,nr=0;
FILE *fin,*fout;
fin=fopen("pairs.in","r");
fscanf(fin,"%ld",&n);
for(x=1;x<=n;x++)
fscanf(fin,"%ld",&m[x]);
for(x=1;x<=n-1;x++)
for(y=2;y<=n;y++)
{ while(m[y])
if(m[x]>m[y])
m[x]=m[x]-m[y];
else m[y]=m[y]-m[x];
if (m[x]==1) nr++;
}
fout=fopen("pairs.out","w");
fprintf(fout,"%ld",nr);
fclose(fin);
fclose(fout);
return 0;
}