C++ :

/*
ID: supersnow0622
PROG: contact
LANG: C++
*/
#include <iostream>
#include <fstream>
#include <string>
#include<memory.h>
#include<algorithm>
using namespace std;
struct Node
{
  int Count,index;
  char str[14];
};
Node n[20000];
int used[20000];
int cmp(Node n1,Node n2)
{
  if(n1.Count==n2.Count)
    return n1.index<n2.index;
  else return n2.Count<n1.Count;
}
int main() {
    ofstream fout ("contact.out");
    ifstream fin ("contact.in");
    int A,B,N;
    string s,temp;
    int count,num;
    cin>>A>>B>>N;
    getline(cin,temp);
    while(getline(cin,temp))
      s+=temp;
    if(s.length()<B)B=s.length();
    for(int i=A;i<=B;i++)
      for(int j=0;j<s.length()-i+1;j++)
      {
         int count=0;num=1;
         while(count<i)
         {
           num=num<<1;
           num=num|(int)(s[j+count]-'0');
           count++;
         }
       n[num].Count++;
       if(n[num].Count==1){
           n[num].index=num;
        for(int k=0;k<i;k++)
         n[num].str[k]=s[k+j];
         }
      }
      sort(n,n+20000,cmp);
      memset(used,0,sizeof(used));
      bool judge=true;count=0;
      for(int i=0;i<20000;i++)
       {
 
         if(n[i].Count!=0){
            if(!used[n[i].Count])
            {
              count++;num=1;
             if(count>N)break;
             if(!judge)cout<<endl;judge=false;
             cout<<n[i].Count<<endl<<n[i].str;
             used[n[i].Count]=1;
            }
            else{
            if(num%6==0)cout<<endl<<n[i].str;
            else cout<<" "<<n[i].str;num++;
            }
          }
       }
       
    return 0;
}

Pascal :

begin
  end.