ll a[2d5],e[2d5],d[2d5];
{
	ll@n,@m,@p,b=0,c=0;
	rd(a(n));
	rep(i,n){
		b>?=a[i];
		while(a[i]%p<1){
			a[i]/=p;
			++e[i];
		}
		c>?=a[i];
	}
	if(b<=m&&c<2){
		wt(-1);
		exit(0);
	}
	d[0]=1;
	rep(i,2d5){
		if(d[i]*b>m){
			wt(i+1);
			exit(0);
		}
		rep(j,n){
			d[i+e[j]+1]>?=d[i]*a[j];
		}
	}
}