func main()
	var n: int :: cui@inputInt()
	var map: [][]int :: #[26, 26]int
	for loop(1, n)
		var s: []char :: cui@input()
		var t: []char :: ##s
		do t.sort()
		if(s <> t)
			skip loop
		end if
		var cs: int :: s[0] $ int - 'a' $ int
		var ce: int :: s[^s - 1] $ int - 'a' $ int
		if(cs = ce)
			do map[cs][ce] :+ ^s
		else
			do map[cs][ce] :: [map[cs][ce], ^s].max()
		end if
	end for
	
	var dp: []int :: #[26]int
	for cs(0, 25)
		for ce(cs, 25)
			do dp[ce] :: [dp[ce], dp[cs] + map[cs][ce]].max()
		end for
	end for
	
	var ans: int :: dp[25]
	do cui@print("\{ans}\n")
end func