!7

p {
  Web web = simpleWeb();
  for (int row = 1; row <= 8; row++)
    for (char col = 'A'; col <= 'H'; col++) {
      rel(web, col, row, (char) (col+1), row, 'right);
      rel(web, col, row, (char) (col-1), row, 'left);
      rel(web, col, row, col, row+1, 'up);
      rel(web, col, row, col, row-1, 'down);
    }
}

svoid rel(Web web, char col1, int row1, char col2, int row2, S rel) {
  S a = cell(col1, row1), b = cell(col2, row2);
  if (nempty() && nempty(b))
    web_relation(web, a, b, rel);
}

sS cell(char col, int row) {
  ret col + str(row);
}