constant s = sq_rand(repeat(repeat(20,20),20))
integer found = 0
for i=1 to 20 do
    for j=1 to 20 do
        printf(1,"%d",s[i][j])
        if s[i][j]=20 then
            found = 1
            exit
        end if
        printf(1,", ")
    end for
    printf(1,"\n")
    if found then exit end if
end for