> #include <iostream>
> #include <string>
> using namespace std;
> class DNA 
> {
> public:
>     DNA (){ left=NULL;right=NULL;}
> 	int n;
> 	string str;
> 	DNA * left;
> 	DNA * right;
> };
> 
> void insert(DNA *,DNA *);
> void type(DNA *);
> int fy(string);
> 
> 
> int main()
> {
> 
> 	DNA *head=new DNA();
>     int n,m;
> 	cin>>n>>m;
> 	int i,j;
> 	cin>>head->str;
> 	head->n=fy(head->str);
> 	for(i=0;i<m-1;i++)
> 	{
> 		DNA *next=new DNA();
> 		cin>>next->str;
> 		next->n=fy(next->str);
> 		insert(head,next);
> 	
> 
> 		
> 	}
> 	type(head);
> 	return 0;
> }
> 
> int fy(string str)
> {
> 	int temp=0;
> 	int i,j;
> 	int n=str.length();
> 	for(i=0;i<n-1;i++)
> 		for(j=i+1;j<n;j++)
> 			if(str[i]>str[j]) temp++;
> 
>     return temp;
> }
> 
> void insert(DNA *first,DNA * nt)
> {
> 	
> 	if( (first->n) <( nt->n) )
> 	{
> 		if(first->right==NULL) first->right=nt;
> 		else insert(first->right,nt);
> 	} else 
> 	{
>         if(first->left==NULL) first->left=nt;
> 		else insert(first->left,nt);
> 	}
> }
> void type(DNA * head)
> {
> 	if(head->left==NULL) 
> 		cout<<head->str;
> 	else type(head->left);
> 	cout<<head->str<<endl;
> 	if(head->right!=NULL) type(head->right);
> }