Give O (N) algorithms to determine whether or not G has a sink, assuming that G is given by its .

Let G be a directed graph with N vertices, A vertex s called sink iff for every v in V such that s != v, there is an
edge ( v , s ) and there is no edges of the form ( s, v ).
Give O (N) algorithms to determine whether or not G has a sink, assuming that G is given by its N*N adjacency
matrix.