If a checker has a neighbourhood of the other color than his then I printed his number (and exit);
else "Draw";
neighbourhood of (x,y) are:
(x+1,y+1)
(x+1,y)
(x+1,y-1)
(x,y+1)
(x,y)
(x,y-1)
(x-1,y+1)
(x-1,y)
(x-1,y-1)
I don't see what's the scope of solving such problems. (except learning english :)) )

still don't understand.

Could you explain it more?

Edited by author 20.10.2004 17:52

Edited by author 20.10.2004 18:07

According to your statement,I wrote a program and got WA on test 3,could you give me some tests or show me your accpeted code to me?

program ural1334;
var
  chess:array[0..9,0..9]of boolean;
  i,x,y:byte;
  a,b:char;
begin
  for i:=0 to 9 do begin
    chess[0,i]:=true;
    chess[9,i]:=true;
  end;
  for i:=1 to 8 do begin
    chess[i,0]:=true;
    chess[i,9]:=true;
  end;

  for i:=1 to 32 do begin
    readln(a,b);
    x:=ord(a)-96;y:=ord(b)-48;
    if (chess[x-1,y-1]<>chess[x+1,y+1]) or (chess[x-1,y+1]<>chess[x+1,y-1]) then begin
      writeln(i);
      halt;
    end;
    chess[x,y]:=true;
  end;
  writeln('Draw');
end.

Edited by author 21.10.2004 10:27

ok this is my code:
#include <iostream.h>
#include <stdlib.h>
int a[10][10];
int free(int x,int y)
{
    if (a[x-1][y-1]==!a[x][y]) return 0;
    if (a[x-1][y+1]==!a[x][y]) return 0;
    if (a[x+1][y-1]==!a[x][y]) return 0;
    if (a[x+1][y+1]==!a[x][y]) return 0;

    if (a[x+1][y]==!a[x][y]) return 0;
    if (a[x-1][y]==!a[x][y]) return 0;
    if (a[x][y+1]==!a[x][y]) return 0;
    if (a[x][y-1]==!a[x][y]) return 0;
    return 1;
}
int main()
{
    char x,y;
    int xx,yy;
    int i,j,t;
    for (i=0;i<10;i++)
    for (j=0;j<10;j++) a[i][j]=-1;
    t=0;
    while (!cin.eof())
    {
        t++;
        cin>>x>>y;
        xx=(int)x-(int)'a'+1;
        yy=(int)y-(int)'1'+1;
        a[xx][yy]=t%2;
        if (!free(xx,yy))
        {
            cout<<t<<"\n";
            exit(0);
        }
    }
    cout<<"Draw\n";
    return 0;
}
It's a stupid problem anyway but I got really angry solving it so that's why i show you the solution.

I'm a Pascaler, so I try my best to understand your C prog. It seems that checkers are not only put in the black cells, but in white cells as well, such as A2, B3 and so on. And also, you mean that a checker can only be felled by a checker belonging to the other player. And you think B1 can fell A1, though in this case B1 will jump off the board! Is the prob statement wrong?