def scan;gets.split.map(&:to_i);end


@n,@m = scan
@ww = scan

@memo = {}
def dfs(idx, lastflg, selected, firstflg)
    return firstflg&&lastflg ? @ww[0] : 0 if idx == @n
    key = [idx, lastflg, selected, firstflg]
    return @memo[key] if @memo[key]
    r = []
    r << ((lastflg ? @ww[idx] : 0) + dfs(idx+1, true, selected+1, firstflg)) if selected < @m
    r << (dfs(idx+1, false, selected, firstflg)) if idx - selected < @n - @m
    return @memo[key] = r.max
end

if @n == @m
    p @ww.inject(:+)
elsif @m <= 1
    p 0
else
    p [dfs(1,false,0,false),dfs(1,true,1,true)].max
end