var i:longint;
begin
 read(i);
 writeln(i-1);
end.

long int c,i;

int main ()
{
     cin>>c;
      cout<<c-1<<endl;

    return 0;
}

Edited by author 16.04.2007 12:51

Edited by author 09.04.2007 20:21

After rejudgment I lost AC. But I think my algo is correct... What's problem?

I don't understand why my solution is uncorrect.
Answer is (k % 3) + 2 . Please give me some test.

[code deleted]

Edited by moderator 09.06.2006 13:40

[code deleted]

Edited by moderator 08.06.2006 08:24

pls tell me where i am mistaking in my logic:
if u take l=k-1 then
whatever the first player takes the second player wins but on test 3 it says wrong anwser

is it possible to be answer zore?
 how?

program ex;
var
  now,i,l,k:longint;
begin
  readln(k);
  now:=k;
  for i:=3 to trunc(sqrt(100000000)) do
   if k mod i=0 then begin now:=i; break; end;
  writeln(now-1);
end.

When I tried to solve this problem, at first I wrote N^3 solution using Dynamic Programming: if we're seeing a piece with length = K and trying solve problem with any L, let's take K-1, K-2, ..., K-L buttons and see, whether second player win with new K and old L. But now we say, that it's first player, because we have already solve this problem for first player and K-1, K-2, ..., 2, 1.
That's all.

Here is my code:

{$APPTYPE CONSOLE}

program buttons;
var
  a: array[1..5000] of integer;
  k: integer;
  i, j, t, x: integer;
  f: boolean;

  function FirstWins(k, l: integer): boolean;
  begin
    Result := (l >= k) or (l < a[k]);
  end;

begin
  read(k);

  a[1] := 0; a[2] := 1;
  for i := 3 to k do
  begin
    for j := 2 to k-1 do
    begin
      f := true;
      for t := i-j to i-1 do
      begin
        if not FirstWins(t, j) then
        begin
          f := false;
          break;
        end;
      end;
      if f then
      begin
        a[i] := j;
        break;
      end;
    end;
  end;

  write(k);
end.

-----------------

After that I observed law: if k mod 3 = 0, print 2 else print n-1:

  read(k);

  if (k mod 3 = 0) then
    write(2)
  else
    write(k-1);

But I got WA in test 6.

Where is my mistake?
Where is mistake in DP-logic?

Edited by author 15.08.2005 10:25

I had AC this problem, but now I have minus for this problem. Why???

1999966
should output 999982
but 1999965 is also correct

var i,k:longint;
    ok:boolean;
begin
 ok:=false;
 readln(k);
 for i:=trunc(sqrt(k)) downto 2 do
  if ((k mod i)=0) and (not ok) then begin
   ok:=true;
   writeln(i);
  end;
 if not ok then writeln(k-1);
end.

I have got A.C.,but my programme doesn't contain the possibility of
output "0".
Actually,you won't find any situation that the number l doesn't
exist,for you can take l=k-1,at least.
So should the problem contain this sentence "If there are no such
numbers, you are to write 0 to the standard output. "???

program permutation;
var
m,p : array [1..1000] of word;
N,i,j : integer;
k : longint;
quit : boolean;
Begin
  readln(N);
  for i := 1 to N do
   read(p[i]);
  for i := 1 to n do
   m[i]:=p[i];
  k:=1;
  quit := false;
  while true do begin
   j:=0;
   repeat
    j:=j+1;
    quit := m[j]=j;
   until (quit=false) or ((i=n) and (m[i]=i));
   if quit then break;
   k:=k+1;
   for i := 1 to n do
    m[i] := p[m[i]];
  end;
  writeln(K);
end.

#include <iostream.h>
#include <math.h>

int main(void)
{
    int K;
    int ind = 1;
    int L = 0;

    cin >> K;

    if( !(K % 2) )
    {
        while( (!(K % 2)) && (K > 4) )
            K /= 2;

        L = K - 1;
        ind = 0;
    };

    for(int i = 3 ; ( i <= ceil( sqrt(K) ) ) && ind ; ++i)
    {
        if( !(K % i) )
        {
            L = i - 1;
            ind = 0;
        };
    };

    if( (K != 1) && (L == 0) )
        L = K - 1;
    cout << L;

    return 0;
};
//I compiled it under bc 3.0, vc 7.0, vc 6.0
//Please HELP

#include <iostream.h>
#include <math.h>
void main()
{   float k;
    long i,l;
cin>>k;
{l=int(k)-1;
for(i=2;i<=sqrt(k)+4;i++) if ((k/i==int(k/i))&& (i>=3) ){l=i-
1;break;};
cout<<l;};
}
always get wrong answer