g=t=a,a=b%a,b=t,g[!a],b
z=({0..100})
while read x y
do((y?t=z[x],z[x]=z[y],z[y]=t:0))
done
r=1
for x in ${z[@]}
{
b=
'++b,j=z[j],j-x&&_'
$[j=x,_,a=r,r*=b/g]
}
echo $r