public void GraphOfTwoVerticesHasNoNegativeCycles()
{
var sut = new NegativeCycleDetectionBellmanFordBased();
var graph =
new[]
{
new WeightedGraphVertex
{
Edges = new System.Collections.Generic.List <WeightedGraphNodeEdge>
{
new WeightedGraphNodeEdge
{
Weight = 1,
To = 1
}
}
},
new WeightedGraphVertex
{
}
};
Assert.False(sut.HasNegativeCycle(graph));
}
public void BaseLine()
{
var sut = new NegativeCycleDetectionBellmanFordBased();
var graph =
new[]
{
new WeightedGraphVertex
{
Edges = new System.Collections.Generic.List <WeightedGraphNodeEdge>
{
new WeightedGraphNodeEdge
{
To = 1,
Weight = 1
}
}
},
new WeightedGraphVertex
{
Edges = new System.Collections.Generic.List <WeightedGraphNodeEdge>
{
new WeightedGraphNodeEdge
{
To = 2,
Weight = 3
}
}
},
new WeightedGraphVertex
{
Edges = new System.Collections.Generic.List <WeightedGraphNodeEdge>
{
new WeightedGraphNodeEdge
{
To = 3,
Weight = 2
}
}
},
new WeightedGraphVertex
{
Edges = new System.Collections.Generic.List <WeightedGraphNodeEdge>
{
new WeightedGraphNodeEdge
{
To = 1,
Weight = -6
}
}
}
};
Assert.True(sut.HasNegativeCycle(graph));
}
public void OneVertexGraphHasNoNegativeCycles()
{
var sut = new NegativeCycleDetectionBellmanFordBased();
var graph =
new[]
{
new WeightedGraphVertex
{
}
};
Assert.False(sut.HasNegativeCycle(graph));
}
public void DistanceIsCalculateForGraphWithCycles()
{
var sut = new NegativeCycleDetectionBellmanFordBased();
var graph =
new[]
{
new WeightedGraphVertex
{
Edges = new System.Collections.Generic.List <WeightedGraphNodeEdge>
{
new WeightedGraphNodeEdge
{
Weight = 1,
To = 1
},
new WeightedGraphNodeEdge
{
Weight = 5,
To = 2
}
}
},
new WeightedGraphVertex
{
Edges = new System.Collections.Generic.List <WeightedGraphNodeEdge>
{
new WeightedGraphNodeEdge
{
Weight = 2,
To = 2
}
}
},
new WeightedGraphVertex
{
Edges = new System.Collections.Generic.List <WeightedGraphNodeEdge>
{
new WeightedGraphNodeEdge
{
Weight = 2,
To = 0
}
}
}
};
Assert.False(sut.HasNegativeCycle(graph));
}
public void DistanceToGrandNeighborNodeIsEqualSumOfEdgesWeight()
{
var sut = new NegativeCycleDetectionBellmanFordBased();
var graph =
new[]
{
new WeightedGraphVertex
{
Edges = new System.Collections.Generic.List <WeightedGraphNodeEdge>
{
new WeightedGraphNodeEdge
{
Weight = 1,
To = 1
}
}
},
new WeightedGraphVertex
{
Edges = new System.Collections.Generic.List <WeightedGraphNodeEdge>
{
new WeightedGraphNodeEdge
{
Weight = 2,
To = 2
}
}
},
new WeightedGraphVertex
{
}
};
Assert.False(sut.HasNegativeCycle(graph));
}
