In this paper, we study the topology of the space of coverings for a 1 dimensional coverage problem. In the sense of full coverage with excess one agent, the topological structure of the space of coverings is described by the skeleton of permutahedron. Based on its topological structure, we design a periodic trajectory which satisfies natural performance requirements and a two-level hybrid hierarchical control on the multi-agent system. Then we compare the hybrid hierarchical control to a usual centralized control through a numerical example and simulations.