public void GivenRandomPopulatedTreeWhenGetPrevReturnsCorrectValue()
{
var tree = new VanEmdeBoasTree64();
var rand = new Random();
var list = new List <ulong>();
for (int i = 0; i < 1 << 17; i++)
{
var elem = GetRandomUlong(rand);
list.Add(elem);
tree.Add(elem);
}
var arr = list.OrderByDescending(x => x).Distinct().ToArray();
if (arr[0] != ulong.MaxValue)
{
Assert.True(tree.TryGetPrevious(ulong.MaxValue, out ulong res));
Assert.Equal(arr[0], res);
}
for (int i = 1; i < arr.Length - 1; i++)
{
if (arr[i - 1] - arr[i] > 1)
{
Assert.True(tree.TryGetPrevious((arr[i - 1] - arr[i]) / 2 + arr[i], out ulong prev));
Assert.Equal(arr[i], prev);
}
Assert.True(tree.TryGetPrevious(arr[i - 1], out ulong res));
Assert.Equal(arr[i], res);
}
Assert.False(tree.TryGetPrevious(arr[arr.Length - 1], out ulong _));
}
public void GivenEmptyTreeWhenTryGetPrevReturnsFalse()
{
var tree = new VanEmdeBoasTree64();
Assert.False(tree.TryGetPrevious(ulong.MaxValue, out ulong _));
}
