graph(Noun) An ordered pair , where is a set of elements called vertices (or nodes) and is a set of pairs of elements of , called edges; informally, a set of vertices together with a set edges that join these vertices.
Clubbing is an enlargement of the ends of the fingers and a downward sloping of the nails. Although it's not caused by chronic obstructive pulmonary disease (COPD), it can be a sign of coexisting lung cancer or other lung disorders in patients with COPD. Clubbing is sometimes called digital clubbing. It can affect the fingers and/or toes.
Causes. Fungal nail infections are caused by various fungal organisms (fungi). The most common cause is a type of fungus called dermatophyte. Yeast and molds also can cause nail infections. Fungal nail infection can develop in people at any age, but it's more common in older adults. As the nail ages, it can become brittle and dry.