@Warshall
PROCEDURE Warshall(a: ARRAY OF ARRAY OF BOOLEAN; V: INTEGER) @=
  BEGIN
  @1 FOR y := 0 TO V-1 DO@
    @2 FOR x := 0 TO V-1 DO@
      @3 IF a[x, y] THEN @
        @4 FOR j := 0 TO V-1 DO @
            @5 IF a[y, j] THEN @ @6 a[x, j] := TRUE @ END; (* if *)                
          END; (* for j *)
        END; (* if *)
      END; (* for x *)
    END; (* for y *)
  END Warshall;
@Warshall
