Data Structures, Algorithms, & Applications in C++
Chapter 7, Exercise 19

(a)

Kennels 2, 3, and 4.

(b)

The matrix is

1 1 0 0 0
1 1 1 0 0
0 1 1 1 0
0 0 1 1 1
0 0 0 1 1

(c)

The matrix is tridiagonal.