private bool IsIntersects(List <MatrixBorder> borders, MatrixBorder testBorder)
{
foreach (var bord in borders)
{
if (bord.Intersect(testBorder))
{
return(true);
}
}
return(false);
}
//Самый очевидный способ. Брут форс. Просто перебираем все возможные прямоугольники, исключаем пересечения, сортируем и выдаем результат
//Время выполнения O(N**4)
private List <MatrixBorder> FindAllOneRectangles(CellObject[,] grid)
{
List <MatrixBorder> borders = new List <MatrixBorder>();
int rows = grid.GetUpperBound(0) + 1;
int columns = grid.GetUpperBound(1) + 1;
for (int rowLower = 0; rowLower < rows; rowLower++)
{
for (int colLower = 0; colLower < columns; colLower++)
{
for (int rowUpper = rowLower; rowUpper < rows; rowUpper++)
{
for (int colUpper = colLower; colUpper < columns; colUpper++)
{
MatrixBorder border = new MatrixBorder {
minRow = rowLower, maxRow = rowUpper, minColumn = colLower, maxColumn = colUpper
};
if (border.IsAllNonZeros(grid) && border.area > 0)
{
borders.Add(border);
}
}
}
}
}
borders.Sort((a, b) => {
return(b.area.CompareTo(a.area));
});
List <MatrixBorder> result = new List <MatrixBorder>();
if (borders.Count > 0)
{
result.Add(borders[0]);
}
for (int i = 1; i < borders.Count; i++)
{
if (!IsIntersects(result, borders[i]))
{
result.Add(borders[i]);
}
}
return(result);
}
private bool IsEqual(MatrixBorder other)
{
return((minRow == other.minRow) && (maxRow == other.maxRow) && (minColumn == other.minColumn) && (maxColumn == other.maxColumn));
}
public bool Intersect(MatrixBorder other)
{
return((minColumn <= other.maxColumn && maxColumn >= other.minColumn && minRow <= other.maxRow && maxRow >= other.minRow) || IsEqual(other));
//return (maxColumn < other.minColumn || other.maxColumn < minColumn || maxRow < other.minRow || other.maxRow < minRow);
}
