TxO Math Bowl 2024 - Team Contest - Problem 20

Charlie is in a slap battle with 4 other people. Starting from Charlie, they take turns choosing someone to slap. When the players decide who to slap, each other player has an equal chance to get slapped, except for the player who just slapped them, who is half as likely as the others to get slapped. What is the expected number of slaps that will occur before Charlie gets slapped for the first time (not counting the slap on Charlie)?