PPP

PPP or ppp may refer to:

Law, business and economics

Medicine

Politics

People's Progressive Party (Gambia)

The People's Progressive Party is a moderate political party in the Gambia. It was the dominant ruling party from 1965 with president Dawda Jawara. He was elected for a sixth term of office in 1992, but was overthrown in a coup by young army officers in 1994. The party was banned from the 1996 and 1997 elections.

In 2005, the PPP joined the opposition National Alliance for Democracy and Development (NADD).

PPP (complexity)

PPP is a complexity class, standing for "Polynomial Pigeonhole Principle". Introduced by Christos Papadimitriou in 1994 (page 528), PPP is a subclass of TFNP. It is a class of search problems that can be shown to be total by an application of the pigeonhole principle.

PPP is defined as follows. A function computation problem belongs to PPP if it admits a polynomial-time reduction to the problem PIGEONHOLE CIRCUIT, in which an input consists of a boolean circuit having the same number of input bits as output bits, and a solution consists of either an input vector that is mapped to the output 0, or alternatively two distinct input vectors that are mapped to the same output. Note that it is the pigeonhole principle that guarantees that a solution must exist. A problem is complete for the class PPP if in addition, PIGEONHOLE CIRCUIT is reducible to that problem.

PPP contains PPAD as a subclass. This is because the corresponding problem that defines PPAD, known as END OF THE LINE, can be reduced (in a straightforward way) to PIGEONHOLE CIRCUIT.