https://www.ifixit.com/Answers/View/949854/What+size+is+the+barrel+jack+port
SOLVED: What size is the barrel jack port? - Lenovo IdeaPad 3-15ALC6 - iFixit
@alberthahn it's a 4mm OD and 1.7mm ID barrel connector that is needed for your IdeaPad - Lenovo IdeaPad 3-15ALC6
lenovo ideapad 3 15alc6