what kind of system of government is Nigeria operating with, cause the presidential system i think they are operating is not really working.system...

Nigeria operates under a federal republican model, based
on that of the United States, with influences from the British Westminster system. Like
in the USA, the president is both head of state and head of
government.

Nigeria's preidential system does work well,
however within the context of Nigerian politics, this is highly subjective. The Nigerian
President fulfils the requirements of the Constitution, but like so much in Nigerian
politics is conducted against a backdrop of of high levels of corruption and
prebendalism.

Nigeria is still regarded as 'democratic',
though the above problems are persistent. Even so, election irregularities are not seen
to be a major problem and do not compromise the overall presidential
system.

Nigeria certainly hasn't reached the point of
despotism or dictatorship.