#include<algorithm>
using namespace std;
int n,l,a[50010];
int ans1,ans2;
int main()
{
	cin>>l>>n;
	int i;
	ans1=0;
	int ans=1000000000;
	for(i=1;i<=n;i++)
	{
		cin>>a[i];
		ans=min(a[i],l-a[i]+1);
		ans1=max(ans1,ans);
	}
	sort(a+1,a+n+1);
	int j,k;
    i=1;
    while(i<n)
    {
    	int h=(a[i+1]+a[i])/2-a[i];
    	ans2=max(ans2,2*h+a[i]);
    	ans2=max(2*h+l+1-a[i+1],ans2);
    	i++;
    }
    	cout<<ans1<<" "<<ans2;
}