The calculation formula of pigeon nest problem is: number of objects ÷ number of pigeon nests = quotient ... remainder, at least number = quotient+1. The problem of pigeon's nest is to put an object in a drawer, and finding the minimum number of objects is the problem of Song's nest. There are enumeration method and hypothesis method to solve the pigeon nest problem.

The origin of pigeon's nest problem: It was first used by German mathematician Dirichlet to solve mathematical problems in19th century.