func main()
	var s: []char :: cui@input()
	var ans: int :: 0
	if(^s > 2)
		var f: int :: 1
		for i(0, ^s - 1)
			var d: int :: s[i] $ int - '0' $ int
			if(d % 3 = 0)
				do ans :+ (d / 3) * 4 ^ (^s - 1 - i)
				if(i = ^s - 1)
					do ans :+ f
				end if
			else
				do ans :+ (d / 3 + 1) * 4 ^ (^s - 1 - i)
				do f :: 0
			end if
		end for
		do ans :+ 14
	else
		var n: int :: s.toInt(&)
		for i(10, n)
			var a: int :: i % 10
			var b: int :: i / 10
			if((a + b) % 3 = 0)
				do ans :+ 1
			end if
		end for
	end if
	do cui@print("\{ans}\n")
end func