Please write answer for N = 169, 841, 674041.

please)

program z1354;

{$APPTYPE CONSOLE}

var mas:array [0..50000] of integer;
    n,i,j,max:integer;
    s:string;
    ch:char;
begin
 s:='';
 while not eof do
  begin
    read(ch);
    if ch in ['a'..'z','A'..'Z'] then
     s:=s+ch;
  end;
 n:=length(s);
 max:=0;
 for i:=1 to n do
  begin
    for j:=n downto i+1 do
      if s[j]=s[n-i+1] then mas[j]:=mas[j-1]+1 else mas[j]:=0;
    if mas[n]>max then max:=mas[n];
  end;
 for i:=1 to n do write(s[i]);
 for i:=n-max downto 1 do write(s[i]);

end.

Is test1 the sample?
I have WA#1 !!!

For whom who use floating K = n / m, try to this test:
3 99  - right answer is 98
99 3  - right answer is 98

my solution WA7, anyone post more test? thanks!

my solution WA7, anyone post more test? thanks!

Anybody have the code on the C?
I thought about it for a long time and i have no ideas how to do this task.
I would be very grateful if somebody help me with it.

There is no single optimal move. There is exactly two moves, one of which is optimal. On every step of greedy, you must choose best of them.

not correct first sample!
12
4
5 3 2 1

correct:

12
4
6 3 2 1

Who can give me some tests(include#5) or hints?

What's the test number 2 ?

1 20 19 18 17
2 21 22 15 16
3 24 23 14 13
4 25 8 9 12
5 6 7 10 11

I have WA5. Give me some explanation and tests please

What may be in test #5?

I think following phrase should be changed:
"Every member of each team must have friends in another team."

Because firstly I thought that every member must have more than 1 friend, since it is "friends".

so something like
"Every member of each team must have at least one friend in another team"
should work

that's so strange
I`m getting WA on test 1
my code prints for sample input #1
1
2
3
1
2
1 2
1 3
1 5
2 3
and for second :
1
2
1
2
1 2
1 4
2 3
3 4
please help me !
thank you