func main()
	var n: int :: cui@inputInt()
	var map: dict<int, int> :: #dict<int, int>
	for(1, n)
		var s: []char :: cui@input()
		var cStart: int
		var cEnd: int
		var len: int
		do f(s, &cStart, &cEnd, &len)
		if(len <> 0)
			var id: int :: cStart + cEnd * 26
			if(cStart = cEnd)
				do map.add(id, map.get(id, &) + len)
			else
				do map.add(id, [map.get(id, &), len].max())
			end if
		end if
		
		func f(s: []char, cStart: &int, cEnd: &int, len: &int)
			for i(1, ^s - 1)
				if(s[i] < s[i - 1])
					do len :: 0
					ret
				end if
			end for
			do cStart :: s[0] $ int - 'a' $ int
			do cEnd :: s[^s - 1] $ int - 'a' $ int
			do len :: ^s
		end func
	end for
	
	var dp: []int :: #[26]int
	for cs(0, 25)
		for ce(cs, 25)
			do dp[ce] :: [dp[ce], dp[cs] + map.get(cs + ce * 26, &)].max()
		end for
	end for
	
	var ans: int :: dp[25]
	do cui@print("\{ans}\n")
end func