Data update

Task/Floyd-Warshall-algorithm/Ada/floyd-warshall-algorithm.ada

@@ -1,183 +0,0 @@
---
--- Floyd-Warshall algorithm.
---
--- See https://en.wikipedia.org/w/index.php?title=Floyd%E2%80%93Warshall_algorithm&oldid=1082310013
---
-
-with Ada.Containers.Vectors;
-with Ada.Text_IO; use Ada.Text_IO;
-with Interfaces;  use Interfaces;
-
-with Ada.Numerics.Generic_Elementary_Functions;
-
-procedure floyd_warshall_task
-is
-  Floyd_Warshall_Exception : exception;
-
-  -- The floating point type we shall use is one that has infinities.
-  subtype FloatPt is IEEE_Float_32;
-  package FloatPt_Elementary_Functions is new Ada.Numerics
-   .Generic_Elementary_Functions
-   (FloatPt);
-  use FloatPt_Elementary_Functions;
-
-  -- The following should overflow and give us an IEEE infinity. But I
-  -- have kept the code so you could use some non-IEEE floating point
-  -- format and set ENORMOUS_FloatPt to some value that is finite but
-  -- much larger than actual graph traversal distances.
-  ENORMOUS_FloatPt : constant FloatPt :=
-   (FloatPt (1.0) / FloatPt (1.0e-37))**1.0e37;
-
-  --
-  -- Input is a Vector of records representing the edges of a graph.
-  --
-  -- Vertices are identified by integers from 1 .. n.
-  --
-
-  type edge is record
-    u      : Positive;
-    weight : FloatPt;
-    v      : Positive;
-  end record;
-
-  package Edge_Vectors is new Ada.Containers.Vectors
-   (Index_Type => Positive, Element_Type => edge);
-  use Edge_Vectors;
-  subtype edge_vector is Edge_Vectors.Vector;
-
-  --
-  -- Floyd-Warshall.
-  --
-
-  type distance_array is
-   array (Positive range <>, Positive range <>) of FloatPt;
-
-  type next_vertex_array is
-   array (Positive range <>, Positive range <>) of Natural;
-  Nil_Vertex : constant Natural := 0;
-
-  function find_max_vertex      -- Find the maximum vertex number.
-   (edges : in edge_vector)
-    return Positive
-  is
-    max_vertex : Positive;
-  begin
-    if Is_Empty (edges) then
-      raise Floyd_Warshall_Exception with "no edges";
-    end if;
-    max_vertex := 1;
-    for i in edges.First_Index .. edges.Last_Index loop
-      max_vertex := Positive'Max (max_vertex, edges.Element (i).u);
-      max_vertex := Positive'Max (max_vertex, edges.Element (i).v);
-    end loop;
-    return max_vertex;
-  end find_max_vertex;
-
-  procedure floyd_warshall      -- Perform Floyd-Warshall.
-   (edges       : in     edge_vector;
-    max_vertex  : in     Positive;
-    distance    :    out distance_array;
-    next_vertex :    out next_vertex_array)
-  is
-    u, v     : Positive;
-    dist_ikj : FloatPt;
-  begin
-
-    -- Initialize.
-
-    for i in 1 .. max_vertex loop
-      for j in 1 .. max_vertex loop
-        distance (i, j)    := ENORMOUS_FloatPt;
-        next_vertex (i, j) := Nil_Vertex;
-      end loop;
-    end loop;
-    for i in edges.First_Index .. edges.Last_Index loop
-      u                  := edges.Element (i).u;
-      v                  := edges.Element (i).v;
-      distance (u, v)    := edges.Element (i).weight;
-      next_vertex (u, v) := v;
-    end loop;
-    for i in 1 .. max_vertex loop
-      distance (i, i) :=
-       FloatPt (0.0);           -- Distance from a vertex to itself.
-      next_vertex (i, i) := i;
-    end loop;
-
-    -- Perform the algorithm.
-
-    for k in 1 .. max_vertex loop
-      for i in 1 .. max_vertex loop
-        for j in 1 .. max_vertex loop
-          dist_ikj := distance (i, k) + distance (k, j);
-          if dist_ikj < distance (i, j) then
-            distance (i, j)    := dist_ikj;
-            next_vertex (i, j) := next_vertex (i, k);
-          end if;
-        end loop;
-      end loop;
-    end loop;
-
-  end floyd_warshall;
-
-  --
-  -- Path reconstruction.
-  --
-
-  procedure put_path
-   (next_vertex : in next_vertex_array;
-    u, v        : in Positive)
-  is
-    i : Positive;
-  begin
-    if next_vertex (u, v) /= Nil_Vertex then
-      i := u;
-      Put (Positive'Image (i));
-      while i /= v loop
-        Put (" ->");
-        i := next_vertex (i, v);
-        Put (Positive'Image (i));
-      end loop;
-    end if;
-  end put_path;
-
-  example_graph : edge_vector;
-  max_vertex    : Positive;
-
-begin
-  Append (example_graph, (u => 1, weight => FloatPt (-2.0), v => 3));
-  Append (example_graph, (u => 3, weight => FloatPt (+2.0), v => 4));
-  Append (example_graph, (u => 4, weight => FloatPt (-1.0), v => 2));
-  Append (example_graph, (u => 2, weight => FloatPt (+4.0), v => 1));
-  Append (example_graph, (u => 2, weight => FloatPt (+3.0), v => 3));
-
-  max_vertex := find_max_vertex (example_graph);
-
-  declare
-
-    distance    : distance_array (1 .. max_vertex, 1 .. max_vertex);
-    next_vertex : next_vertex_array
-     (1 .. max_vertex, 1 .. max_vertex);
-
-  begin
-
-    floyd_warshall (example_graph, max_vertex, distance, next_vertex);
-
-    Put_Line ("  pair       distance        path");
-    Put_Line ("---------------------------------------------");
-    for u in 1 .. max_vertex loop
-      for v in 1 .. max_vertex loop
-        if u /= v then
-          Put (Positive'Image (u));
-          Put (" ->");
-          Put (Positive'Image (v));
-          Put ("    ");
-          Put (FloatPt'Image (distance (u, v)));
-          Put ("    ");
-          put_path (next_vertex, u, v);
-          Put_Line ("");
-        end if;
-      end loop;
-    end loop;
-
-  end;
-end floyd_warshall_task;

Task/Floyd-Warshall-algorithm/Pluto/floyd-warshall-algorithm.pluto

@@ -1,5 +1,4 @@
 require "table2"
-require "math2"
 
 class floydWarshall
     static function do_calcs(weights, nvertices)