const x:array[1..26]of longint=(1,1,2,3,5,8,13,21,34,55,89,144,233,377,610,987,1597,2584,4181,6765,10946,   
17711,28657,46368,75025,121393);   
  
var f,g:text;   
    a:array[1..3500000] of char;   
    k,pas,i,j,ii,n:longint;   
    ok:boolean;   
begin  
  
assign(f,'lampa.in'); reset(f);   
assign(g,'lampa.out'); rewrite(g);   
  
readln(f,pas,n);   
  
for i := 1 to n do read(f,a[i]);   
  
if pas mod 2 = 0 then begin  
i:=n;   
ok:=false;   
 repeat  
   for i := i downto 1 do  
          if a[i]= a[1] then break;   
   j:=0;ii:=i-1;   
   while a[j+1]=a[ii+1] do begin  
                  inc(j);   
                  inc(ii);   
                       end;   
   if ii=n then ok := true;   
 until ok;   
 ii:=i;   
 for i:= i-1 downto 1 do  
      if (a[i]=a[n])and(a[i-1]=a[n-1]) then break;   
  
                       end; 

for i := 1 to j do write(g,a[i]);  
for k:= i+1 to ii-1 do write(g,a[k]); writeln(g);   
   
close(f);   
close(g);   
end.