public static void RainWaterTrap()
{
List <int> traps = new List <int>()
{
0, 1, 0, 2, 1, 0, 1, 3, 2, 1, 2, 1
};
Assert.That(ArrayQ.RainWaterTrap(traps) == 6);
Assert.That(ArrayQ.RainWaterTrap2(traps) == 6);
}