2013 ToT Spring Senior O p4 100 stones have a sticker showing its true weight
Source:
March 5, 2020
weighingscombinatorics
Problem Statement
Each of stones has a sticker showing its true weight. No two stones weight the same. Mischievous Greg wants to rearrange stickers so that the sum of the numbers on the stickers for any group containing from to stones is different from the true weight of this group. Is it always possible?