Page 277, Exercise 2 (a)

  0 1 2 3 4 5 Out-Degree
0 0 0 0 0 0 0 0
1 1 0 0 1 0 0 2
2 0 1 0 0 0 1 2
3 0 0 1 0 1 1 3
4 1 0 0 0 0 0 1
5 1 1 0 0 1 0 3
In-Degree 3 2 1 1 2 2  

2(b) Adjacency list

Vertex 0 NULL

Vertex 1 -> 0 -> 3 -> NULL
Vertex 2 -> 1 -> 5 -> NULL
Vertex 3 -> 2 -> 4 -> 5 -> NULL
Vertex 4 -> 0 -> NULL
Vertext 5 -> 0 -> 1 -> 4 -> NULL
2(C) ADJACENCY MULTII-LIST
 HeadNodes                      Multilist Nodes 
      ______________________________________________________________________________________________
  0   NULL          N1  -> 1   ->0   ->N2   ->NULL   edge (1,0)     
  1   -> N1         N2  -> 1   ->3   ->NULL ->N5     edge(1,3) 
  2   -> N3         N3  -> 2   ->1   ->N4   ->NULL   edge(2,1)
  3   -> N5         N4  -> 2   ->5   ->NULL ->N9     edge(2,5)     
  4   -> N8         N5  -> 3   ->2   ->N6   ->NULL   edge(3,2)
  5   -> N9         N6  -> 3   ->4   ->N7   ->N8     edge(3,4)                 
                    N7  -> 3   ->5   ->NULL ->N9     edge(3,5) 
                    N8  -> 4  ->0    ->NULL ->NULL   edge(4,0) 
                    N9  -> 5  ->0    ->N10  ->NULL   edge(5,0)       
                    N10  -> 5  ->1   ->N11  ->NULL   edge(5,1) 
                    N11  -> 5   ->4  ->NULL  ->NULL   edge(5,4) 
                     
                    The lists are: 
 
 
  vertex 0: NULL 
  vertex 1: N1     N2 
  vertex 2: N3     N4 
  vertex 3: N5     N6     N7 
  vertex 4: N8 
  vertex 5: N9     N10     N11                 
(e) Since node 0 has an out-degree of 0, it is not strongly connected. Similarly, since node 4's only outward node is adjacent to node 0, it is not strongly connected. The remaining nodes are all strongly connected as the table below illustrates.
                                                           
V i   V j       v i  ->v j      v j  -> v i  
                                                            
1      2       <1,3><3,2>         <1,2>     
1      3       <1,3>              <3,2><2,1> 
1      5       <1,3><3,5>         <5,1>     
2      3       <2,1><1,3>         <3,2>     
2      5       <2,5>              <5,1><1,3><3,2> 
3      5       <3,5>              <5,1><1,3>