public void GivenSingleSourceSingleDestinationWhenFindMaximumFlowThenWorksFine()
{
// arrange
var source = new SimpleNode("START");
var destination = new SimpleNode("DESTINATION");
var arcs = new List <IArcWithFlow <SimpleNode> >
{
new SimpleArcWithFlow <SimpleNode>(source, destination, 1),
};
// act & assert
Assert.DoesNotThrow(() => arcs.FindMaximumFlow());
}
public void GivenCycledLoopsWhenTryToFindMaximumFlowThenThrowError()
{
// arrange
var a = new SimpleNode("A");
var b = new SimpleNode("B");
var arcs = new List <IArcWithFlow <SimpleNode> >
{
new SimpleArcWithFlow <SimpleNode>(a, b, 1),
new SimpleArcWithFlow <SimpleNode>(b, a, 1),
};
// act & assert
Assert.Throws <ArgumentException>(() => arcs.FindMaximumFlow());
}
public void GivenTwoDestinationsWhenTryToFindMaximumFlowThenThrowError()
{
// arrange
var source = new SimpleNode("START");
var destination1 = new SimpleNode("DESTINATION_1");
var destination2 = new SimpleNode("DESTINATION_2");
var arcs = new List <IArcWithFlow <SimpleNode> >
{
new SimpleArcWithFlow <SimpleNode>(source, destination1, 1),
new SimpleArcWithFlow <SimpleNode>(source, destination2, 1),
};
// act & assert
Assert.Throws <ArgumentException>(() => arcs.FindMaximumFlow());
}
public void GivenOneArcWhenFindMaximumFlowThenReturnItsFlow()
{
// arrange
var source = new SimpleNode("START");
var destination = new SimpleNode("DESTINATION");
var arcs = new List <IArcWithFlow <SimpleNode> >
{
new SimpleArcWithFlow <SimpleNode>(source, destination, 123),
};
// act
double maxFlow = arcs.FindMaximumFlow(source, destination);
// assert
Assert.AreEqual(123, maxFlow);
}
public void GivenNoArcsFromStartWhenFindShortestPathsThenReturnEmpty()
{
// arrange
var start = new SimpleNode("START");
var a = new SimpleNode("A");
var b = new SimpleNode("B");
var arcs = new IArcWithLength <SimpleNode>[]
{
new SimpleArcWithLength <SimpleNode>(a, b, 10),
};
// act
var foundPaths = arcs.FindShortestPaths(start);
// assert
Assert.AreEqual(0, foundPaths.Count);
}
public void GivenParallelArcsWhenFindMaximumFlowThenReturnTheirSummary()
{
// arrange
var source = new SimpleNode("START");
var destination = new SimpleNode("DESTINATION");
var arcs = new List <IArcWithFlow <SimpleNode> >
{
new SimpleArcWithFlow <SimpleNode>(source, destination, 123),
new SimpleArcWithFlow <SimpleNode>(source, destination, 456),
new SimpleArcWithFlow <SimpleNode>(source, destination, 789),
};
// act
double maxFlow = arcs.FindMaximumFlow(source, destination);
// assert
Assert.AreEqual(123 + 456 + 789, maxFlow);
}
public void GivenLinearChainWhenFindMaximumFlowThenReturnMinimumFlow()
{
// arrange
var a = new SimpleNode("A");
var b = new SimpleNode("B");
var c = new SimpleNode("C");
var d = new SimpleNode("D");
var arcs = new List <IArcWithFlow <SimpleNode> >
{
new SimpleArcWithFlow <SimpleNode>(a, b, 567),
new SimpleArcWithFlow <SimpleNode>(b, c, 123),
new SimpleArcWithFlow <SimpleNode>(c, d, 234),
};
// act
double maxFlow = arcs.FindMaximumFlow(a, d);
// assert
Assert.AreEqual(123, maxFlow);
}
public void GivenChainWhenFindShortestPathsThenReturnSimple()
{
// arrange
var start = new SimpleNode("START");
var a = new SimpleNode("A");
var b = new SimpleNode("B");
var c = new SimpleNode("C");
var arcs = new IArcWithLength <SimpleNode>[]
{
new SimpleArcWithLength <SimpleNode>(start, a, 1),
new SimpleArcWithLength <SimpleNode>(a, b, 2),
new SimpleArcWithLength <SimpleNode>(b, c, 3),
};
// act
var foundPaths = arcs.FindShortestPaths(start);
// assert
Assert.AreEqual(3, foundPaths.Count);
Assert.AreEqual(1, foundPaths.First(p => p.To == a).Lenght);
Assert.AreEqual(3, foundPaths.First(p => p.To == b).Lenght);
Assert.AreEqual(6, foundPaths.First(p => p.To == c).Lenght);
}
private static ulong getWeight(SimpleNode item)
{
return(item.Weight);
}