v100s3e4

#include<iostream>
using namespace std;
int main()
 {
  int x,lv,ln,k;
  char s[10000];
  cin>>x>>k;
  cin>>s;
  if(x<9)
   {
    lv=1;
    ln=1;
    }
   if(x==9)
    {
     lv=1;
     ln=2;
    }
   if(x>9)
    {
     lv=2;
     ln=2;
    }

  while(ln<k)
   {
    ln=ln+lv;
    lv=ln-lv;
   }
  s[k-lv+1]=0;
  cout<<s;
 }