Please subscribe to the official Codeforces channel in Telegram via the link ×


By _QWOiNYUIVMPFSBKLiGSMAP_, history, 6 years ago, In English

Hello everyone i was solving a problem which wants the number of faces in a planar graph of N nodes E edges. it is solvable by euler formula but what is the proof of this formula this link has alot of helpful proofs but i could understand the 3rd proof if anyone intersting in understanding it please explain it to me.

thanks in advance :)