public void Can_identify_that_empty_matrix_has_no_saddle_points()
{
var input = new int[, ] {
};
var sut = new SaddlePoints(input);
var actual = sut.Calculate();
Assert.Empty(actual);
}
public void Can_identify_single_saddle_point()
{
var matrix = new[, ]
{
{ 9, 8, 7 },
{ 5, 3, 2 },
{ 6, 6, 7 }
};
var actual = SaddlePoints.Calculate(matrix);
var expected = new[] { (2, 1) };
public void Can_identify_lack_of_saddle_points_when_there_are_none()
{
var input = new[, ] {
{ 1, 2, 3 }, { 3, 1, 2 }, { 2, 3, 1 }
};
var sut = new SaddlePoints(input);
var actual = sut.Calculate();
Assert.Empty(actual);
}
public void Can_identify_saddle_point_in_bottom_right_corner()
{
var input = new[, ] {
{ 8, 7, 9 }, { 6, 7, 6 }, { 3, 2, 5 }
};
var sut = new SaddlePoints(input);
var actual = sut.Calculate();
var expected = new[] { Tuple.Create(2, 2) };
Assert.Equal(expected, actual);
}
public void Can_identify_multiple_saddle_points()
{
var input = new[, ] {
{ 4, 5, 4 }, { 3, 5, 5 }, { 1, 5, 4 }
};
var sut = new SaddlePoints(input);
var actual = sut.Calculate();
var expected = new[] { Tuple.Create(0, 1), Tuple.Create(1, 1), Tuple.Create(2, 1) };
Assert.Equal(expected, actual);
}
public void Can_identify_single_saddle_point()
{
var input = new[, ]
{
{ 9, 8, 7 },
{ 5, 3, 2 },
{ 6, 6, 7 }
};
var sut = new SaddlePoints(input);
var actual = sut.Calculate();
var expected = new[] { Tuple.Create(1, 0) };
Assert.Equal(expected, actual);
}
public void Can_identify_saddle_point_in_large_matrix()
{
var input = new int[1000, 1000];
for (var i = 0; i < input.GetLength(0); i++)
{
for (var j = 0; j < input.GetLength(1); j++)
{
input[i, j] = (i + 1) * (j + 1);
}
}
var sut = new SaddlePoints(input);
var actual = sut.Calculate();
var expected = new[] { (0, input.GetLength(1) - 1).ToTuple() };