Problem

Source: 2022 Saudi Arabia January Camp Test 1.4 BMO + EGMO TST

Tags: combinatorics, combinatorial geometry, tiles, Tiling



The sword is a figure consisting of $6$ unit squares presented in the picture below (and any other figure obtained from it by rotation). Determine the largest number of swords that can be cut from a $6\times 11$ piece of paper divided into unit squares (each sword should consist of six such squares).