func main() {
ReadMatrix("p082_matrix.txt")
graph := digraph.Graph{make([]digraph.Node, N*N+2)}
A := N * N // supersource
B := N*N + 1 // supersink
// Set up supersource
graph.Nodes[A].Neighbors = make([]digraph.Edge, N)
for i := 0; i < N; i++ {
graph.Nodes[A].Neighbors[i].To = Idx(i, 0)
graph.Nodes[A].Neighbors[i].Weight = mat[i][0]
}
for i := 0; i < N; i++ {
for j := 0; j < N; j++ {
nodeIdx := Idx(i, j)
// Add edge upwards if possible
if i != 0 {
graph.Nodes[nodeIdx].Neighbors =
append(graph.Nodes[nodeIdx].Neighbors, digraph.Edge{Idx(i-1, j), mat[i-1][j]})
}
// Add edge downwards if possible
if i != N-1 {
graph.Nodes[nodeIdx].Neighbors =
append(graph.Nodes[nodeIdx].Neighbors, digraph.Edge{Idx(i+1, j), mat[i+1][j]})
}
// Add edge rightwards if possible
if j != N-1 {
graph.Nodes[nodeIdx].Neighbors =
append(graph.Nodes[nodeIdx].Neighbors, digraph.Edge{Idx(i, j+1), mat[i][j+1]})
}
}
}
// Set up supersink
for i := 0; i < N; i++ {
graph.Nodes[Idx(i, N-1)].Neighbors =
append(graph.Nodes[Idx(i, N-1)].Neighbors, digraph.Edge{B, 0.0})
}
dist, _ := digraph.Dijkstra(graph, A)
fmt.Printf("%v\n", dist[B])
}
func main() {
ReadMatrix("p083_matrix.txt")
//ReadMatrix("smallmatrix.txt")
graph := digraph.Graph{make([]digraph.Node, N*N)}
for i := 0; i < N; i++ {
for j := 0; j < N; j++ {
nodeIdx := Idx(i, j)
// Add edge upwards if possible
if i != 0 {
graph.Nodes[nodeIdx].Neighbors =
append(graph.Nodes[nodeIdx].Neighbors, digraph.Edge{Idx(i-1, j), mat[i-1][j]})
}
// Add edge downwards if possible
if i != N-1 {
graph.Nodes[nodeIdx].Neighbors =
append(graph.Nodes[nodeIdx].Neighbors, digraph.Edge{Idx(i+1, j), mat[i+1][j]})
}
// Add edge rightwards if possible
if j != N-1 {
graph.Nodes[nodeIdx].Neighbors =
append(graph.Nodes[nodeIdx].Neighbors, digraph.Edge{Idx(i, j+1), mat[i][j+1]})
}
// Add edge rightwards if possible
if j != 0 {
graph.Nodes[nodeIdx].Neighbors =
append(graph.Nodes[nodeIdx].Neighbors, digraph.Edge{Idx(i, j-1), mat[i][j-1]})
}
}
}
dist, _ := digraph.Dijkstra(graph, Idx(0, 0))
fmt.Printf("%v\n", mat[0][0]+dist[Idx(N-1, N-1)])
}