3

0

1

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Euler line

Complete Graph

Hamiltonian Cycle

Bipartite graph

all its vertices have even degree

there is a spanning tree in the graph

there is a path between any two vertices of the graph

there are even n umber of vertices with odd degree

complete graph

multigraph

simple graph

general graph

Any closed walk that contains all the edges of the graph is an Eulerline.

Any closed walk that contains all the vertices of the graph is an Eulerline.

Every closed walk is an Eulerline also.

Edges are can be traced more than once in a walk while its not so in an Eulerline. 

The number of vertices decreases by one but edge count remains the same.

The number of vertices decreases by one.

The number of edges decreases by one.

any one of (a), (b) and (c).

vertices

edges and vertices 

edges

Every vertex does not have even degree

There are several bridges

There is no path between some bridges

All vertices have distinct degrees

1

7

15

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