Np Problem Example Math
Many significant computer science problems belong to this class e g the traveling salesman problem satisfiability problems and graph covering problems.
Np problem example math. Displaystyle ax 2 by c 0 quadratic programming np hard in some cases p if convex subset sum problem. 1 l is in np any given solution for np complete problems can be verified quickly but there is no efficient known solution. So called easy or tractable problems can be solved by computer algorithms that run in polynomial time. Another example until recently was the set of composite numbers.
Np complete problems are the hardest problems in np set. The graph isomorphism problem the discrete logarithm problem and the integer factorization problem are examples of problems believed to be np intermediate. The graph isomorphism problem is the computational problem of determining whether two finite graphs are isomorphic. 2 every problem in np is reducible to l in polynomial time reduction is defined below.
Np complete problem any of a class of computational problems for which no efficient solution algorithm has been found. I e for a problem of size n the time or number of steps needed to find the solution is a polynomial function of n. Perhaps the most famous exponential time problem in np for example is finding prime factors of a large number. An obvious solution is to check all possibilities.
Sudoku is an np problem hard to solve easy to check. Given two undirected graphs determine whether they are isomorphic. P equals np is a hotly debated millennium prize problem one of a set of seven unsolved mathematical problems laid out by the clay mathematical institute each with a 1 million prize for those. Verifying a solution just requires multiplication but solving the problem seems to require systematically trying out lots of candidates.
A b c 0. Displaystyle x y such that. A decision problem l is np complete if. Displaystyle textstyle a b c geq 0 find positive integers.
They are some of the very few np problems not known to be in p or to be np complete. A x 2 b y c 0. But this only works for small problems. One example is the graph isomorphism problem.
You know all the distances. Another important example today is factoring large numbers into prime numbers. There are interesting examples of np problems not known to be either in p or np complete.