4. a) Hamilton Path  is  a  simple path in a graph that passes

        through every vertex exactly once.

 

Example:

G₁ has a Hamilton path, a, b, c, d

 

 

b) Hamilton Circuit  is a simple circuit in a graph that passes    through every vertex exactly once.

 

Example:

G₂ has a Hamilton circuit: a, b, c, d, e, a