my idea for solution
  k := 2;
  n := length(s);
  s1 := s[1];
  while true do begin
    i := 0;
    while (n - i >= k + i) and (s[k + i] = s[n - i]) do inc(i);
    if n - i <= k + i
    then begin
      write(s + s1);
      halt;
    end;
    s1 := s[k] + s1;
    inc(k);
  end;

In Russian, the name of the problem is noncomformizm, it should be nonco_n_formizm.

В чем ошибка?
#include<stdio.h>
#include<math.h>
void main()
{
    int n,k=0,i=1,j,m;
    scanf("%d",&n);
    for(j=1;j<=n;j++)
    {
    m=pow(10,j);
    while (i<m)
    {
        if (i*i%m==i) {k++; printf("\n%d %d",i,i*i);}
        if (i%10==1) i=i+4; else
        if (i%10==5) i++;    else
        if (i%10==6) i=i+5;
    }
    }
    printf("%d",k);
}

I'm pretty sure that testset for this problem doesn't contain maxitests with k=2 and n=22. Otherwise how could program that works about 20sec. on my computer get AC on timus???

No recursion or brute force would needed, if you could guess some regularity. Of course this requires some thoughts from you ;)

My main() contains only these lines but input:

if(canWinNow('X') > 0 || existsMagicCell('X')) CROSSESWIN
else if(canWinNow('O') > 1) OUTHSWIN
else DRAW

What canWinNow() does you may guess yourself, and existsMagicCell() contains about 10 lines and is not recursive.

Who wants to find out my algo write a-zakh [at] yandex.ru

Hey,
Can anyone tell me what is test 28?? I have time limit exceeded?

This is my code:
program Monobilliards_1494;

var
  tmp, b, a, i, n: LongInt;
  x: array [1..100000] of LongInt;
  cheater: boolean;

begin
  cheater := false;
  readln(n);
  for i := 1 to n do readln(x[i]);

  i := 1;
  tmp := x[1] - 1;
  while (i <= n) and not cheater do begin
    if tmp < x[i] then begin
      b := x[i] - i;
      tmp := x[i];
      a := i + 1;
      while (a <= n) and (b > 0) do begin
        if tmp > x[a] then begin
          b := b - 1;
          tmp := x[a];
        end;
        a := a + 1;
      end;
    end;
    tmp := x[i];
    if b > 0 then cheater := true;
    i := i + 1;
  end;

  if cheater then writeln('Cheater')
  else writeln('Not a proof');
end.

I have WA#10. Can you help me?
here is my code:
program _1191;

{$APPTYPE CONSOLE}

uses
  SysUtils;

var   k:array[1..100]of longint;
l,n,i,q,z:longint;
begin
reset(input,'input.txt');
 rewrite(output,'ouput.txt');
  read(l,n);
  q:=1;
  z:=0;
  for i:=1 to n do
    begin
     read(k[i]);
     z:=z+k[i];
     if l<z then
        begin
          write('YES');
          halt(0);
        end
     else
      while l>z+q*k[i] do
        inc(q);
      l:=z+q*k[i];
        q:=1;
    end;
   write('NO');
end.

Edited by author 18.03.2009 19:38

var a:array [1..50] of byte;
    i,n,q:byte;
    ch:char;
    k:longint;
begin
  i:=0;
  while not(eoln) do
    begin
      inc(i);
      read(ch);
      a[i]:=ord(ch)-48;
    end;
  n:=i;
  q:=0;
  for i:=n downto 1 do
    begin
      inc(q);
      if q mod 7=1 then k:=k+(a[i]);
      if q mod 7=2 then k:=k+(a[i]*3);
      if q mod 7=3 then k:=k+(a[i]*2);
      if q mod 7=4 then k:=k+(a[i]*6);
      if q mod 7=5 then k:=k+(a[i]*4);
      if q mod 7=6 then k:=k+(a[i]*5);
    end;
  writeln(k mod 7);
  readln;
end.
WA #2 test...

I have WA on second test! Please help me!
PS Sorry fr bag English

I try to find fib(2*n-2)/fib(n-2) but I get TL on test 4, my algo is linear so I couldn't pass the TL, I wonder is the direct algo for finding fib(n-2) and fib(2*n-2) better, because I couldn't implement it :)

#include <cstdio>
#include <string>
#include <memory>
using namespace std;

class BigInteger{
private:
  enum{MAXLENGTH=14900};
  int m[MAXLENGTH];
  int len;

public:
  BigInteger(int n)
  {
    memset(m,0,sizeof(m));
    len=0;
    if (n == 0) len++;
    while (n > 0)
    {
      m[len++] = n % 10;
      n = n / 10;
    }
  }

  BigInteger(void)
  {
    memset(m,0,sizeof(m));
    len=1;
  }


  void print(void)
  {
    int temp = len-1;
    while(temp>=0) printf("%d",m[temp--]);
  }

  BigInteger operator+ (const BigInteger &a)
  {
    int i,carry = 0;
    BigInteger Temp(*this);
    if (a.len > Temp.len) Temp.len = a.len;
    for(i=0;i<Temp.len;i++)
    {
      Temp.m[i] += (a.m[i] + carry);
      carry =  Temp.m[i] / 10;
      Temp.m[i] %= 10;
    }
    if (carry > 0) {Temp.m[i] = carry; Temp.len++;}
    return Temp;
  }








  int operator> (const BigInteger &a)
  {
    int i;
    if (len > a.len) return 1;
    if (len < a.len) return 0;
    for(i=len-1;(m[i] == a.m[i]) && (i>0);i--);
    if (m[i] > a.m[i]) return 1;
    return 0;
  }
int operator== (const BigInteger &a)
  {
    int i;
    if (len != a.len) return 0;
    for(i = len-1;i>=0;i--)
      if (m[i] != a.m[i]) return 0;
    return 1;
  }

};
int main()
{
    int n;

scanf("%d",&n);
BigInteger r1;int i;
    BigInteger previous = -1;
    BigInteger result = 1;
    for (i = 0; i<n; i++)
    {
    BigInteger const sum = result + previous;
    previous = result;
    result = sum;
    if(i==n-3){
    r1=result;
    }
    }
    (r1+result).print();
return 0;
}


Edited by author 25.09.2008 01:10

Thanks a lot.

Why this gets WA1?

//---------------------------------------------------------------------------
#include <iostream.h>
#include <memory.h>
int main()
{
        bool mas[30][30];
        for (int i=0; i<30; ++i)
        for (int j=0; j<30; ++j)
        {
                mas[i][j]=false;
        }
        int n;
        char ch,ch1,ch2;
        cin>>n;
        for (int i=0; i<n; ++i)
        {
                cin>>ch1>>ch2;
                mas[ch1-'a'][ch2-'a']=true;
        }
        cin>>ch;
        for (int i=0; i<30; ++i)
        {
                if (mas[ch-'a'][i])
                {
                        cout<<ch<<(char)(i+'a')<<endl;
                }
        }
        cin>>ch;
        return 0;
}
//---------------------------------------------------------------------------

#include <iostream.h>
int main()
{ const int n=30;
int a[n][n], i, N,j,k;
cin>>N;
for(i=0; i<N; i++)
for(j=0; j<N; j++) cin>>a[i][j];
cin>>k;
for(j=0; j<n; j++) cout<<a[k][j];
 return 0; }

#include<iostream>
using namespace std;
int main () {
int a[3000],b[3000],c[3000];
long long int i,j,k,n,m;
cin>>n>>m;
for (i=0;i<n;i++){
    cin>>a[i];
    for(j=0;j<m;j++){
                     cin>>a[j];
                     }
                    {
                         c[j]= a[j] + b[j];
                         }
                         for (j=0;j<m-1;j++){
                             if ((c[j] = 1) && (c[j+1] = 2) || (c[j] = 2) && (c[j+1] >= 1))
{
                             cout<<"NO";

                            return 0;
                             }
                            else    { cout<<"YES";}
                             }
                             }

                             return 0;
                             }

    Why I WA on #8?I can't find what's wrong with my program.
    Here is my code:
    program jamaica;
const
  maxn=310;
var
  k,b,l:array [0..maxn*maxn] of extended;
  x,y:array [0..maxn] of int64;
  i,j,m,n,min,max:longint;
  ans,d:double;
procedure init;
  begin
    readln(n);
    for i:=1 to n do readln(x[i],y[i]);
  end;
procedure qsort(head,tail:longint);
  var
    i,j,t,k:longint;
  begin
    if head>=tail then exit;
    i:=head;j:=tail;
    t:=x[(i+j) shr 1];
    repeat
     while x[j]>t do dec(j);
     while x[i]<t do inc(i);
     if i<=j
       then begin
              k:=x[i];x[i]:=x[j];x[j]:=k;
              k:=y[i];y[i]:=y[j];y[j]:=k;
              inc(i);dec(j);
            end;
    until i>=j;
    qsort(head,j);
    qsort(i,tail);
  end;
procedure sort(head,tail:longint);
  var
    i,j:longint;
    x,y,t:double;
  begin
    if head>=tail then exit;
    i:=head;j:=tail;
    x:=k[(i+j) shr 1];y:=b[(i+j) shr 1];
    repeat
     while (k[j]-x>1e-8) or (abs(k[j]-x)<1e-8) and (b[j]-y>1e-8) do dec(j);
     while (k[i]-x<-1e-8) or (abs(k[i]-x)<1e-8) and (b[i]-y<-1e-8) do inc(i);
     if i<=j
       then begin
              t:=k[i];k[i]:=k[j];k[j]:=t;
              t:=b[i];b[i]:=b[j];b[j]:=t;
              t:=l[i];l[i]:=l[j];l[j]:=t;
              inc(i);dec(j);
            end;
    until i>=j;
    sort(head,j);
    sort(i,tail);
  end;
procedure solve;
  begin
    qsort(1,n);
    ans:=0;
    min:=y[1];max:=y[1];
    for i:=2 to n do
      if x[i]<>x[i-1]
        then begin
               ans:=ans+max-min;
               max:=y[i];min:=y[i];
             end
        else begin
               if y[i]>max then max:=y[i];
               if y[i]<min then min:=y[i];
             end;
    ans:=ans+max-min;
    m:=0;
    for i:=1 to n-1 do
      for j:=i+1 to n do
        if x[i]<>x[j]
          then begin
                 inc(m);k[m]:=(y[j]-y[i])/(x[j]-x[i]);b[m]:=y[i]-k[m]*x[i];
                 l[m]:=sqrt(sqr(x[i]-x[j])+sqr(y[i]-y[j]));
               end;
    sort(1,m);
    d:=l[1];
    for i:=2 to m do
      if (k[i]<>k[i-1]) or (b[i]<>b[i-1])
        then begin
               ans:=ans+d;
               d:=l[i];
             end
        else begin
               if l[i]>d then d:=l[i];
             end;
    ans:=ans+d;
  end;
begin
  init;
  solve;
  writeln(round(ans));
end.

I know AC solution that answers 3 2 1 for test
3
0
3 0
1 0
The only right answer for this test is 2 3 1

Crash, because in Input numbers t1, t2, t3 separeted more then one space.
So, I replaced
string[] ss = Console.ReadLine().Split(' ');
to
string[] ss = Console.ReadLine().Split(new char[]{' '},StringSplitOptions.RemoveEmptyEntries);
and got AC.

type
TStack=class(TObject)
public
Data:Extended;
Next:TStack;
function Add(AData:Extended):TStack;
function Delete:TStack;
end;
function TStack.Add(AData:Extended):TStack;
begin
Result:=TStack.Create;
Result.Data:=AData;
Result.Next:=Self
end;
function TStack.Delete:TStack;
begin
Result:=Next;
Free;
end;
var Stack:TStack;
AData:Extended;
begin
Stack:=nil;
while not eof do
begin
Read(AData);
Stack:=Stack.Add(AData)
end;
while Stack<>nil do
begin
Writeln(Sqrt(Stack.Data));
Stack:=Stack.Delete
end;
end.