A simple graph consists of , a nonempty set of vertices, and , a - PowerPoint PPT Presentation

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❷ ❅ ✶ ✽ ✾ ✿ ❀❁ ❂ ❃ ✵ ✷ ❁❄ ❀ ✳ ✺ ❆ ❇ ❃ ✱ ✼ ✹ ❃ ✱ ✺ ❈ ✹ ✻✼ ✹ ✟ ❑ ❜ ✆ ☎ ③ ✁ ☎ ✄ ✟ ✁ ✝ ✂ ❸ ✸ ▲ ▲ ❑ ✰✱✲ ✳ ✴ ✵ ✶✷ An Euler circuit in a graph is a simple circuit containing every edge of . Theorem: A connected multigraph has an Euler circuit if and only if each of its vertices has even degree.