HIGHEST BLOCK jak wybrac

Jak w ten komendzie zamiast random element zrobic zeby skrypt wybieral najwyzszy Y czyli jakby highest block

command /PUSTO2 [<number>]:
    trigger:
        loop blocks in radius 35 around player:
            if loop-block is red_concrete:
                if block above loop-block is air:
                    add loop-block's location to {_locs::*}
        set {_loc} to random element of {_locs::*}
        add 4 to y-location of {_loc}
        teleport player to {_loc}

nie dzialaja takie opcje jak: 

set {_loc} to highest element of {_locs::}
set {_loc} to highest block of {_locs::}
set {_loc} to highest solid block of {_locs::*}