func main()
	var n: int :: cui@inputInt()
	var ans: modInt :: (#modInt).init(10, 1000000007)
	do ans.pow(n)
	do ans.mul(4)
	do ans.sub(1)
	do ans.div(3)
	do cui@print("\{ans}\n")
	
	; val, mod, a, b: 0 to 2 ^ 31.
	class modInt()
		var val: int
		var mod: int
		+func init(val: int, mod: int): modInt
			do me.val :: val % mod
			do me.mod :: mod
			ret me
		end func
		+func add(a: int): modInt
			do me.val :+ a
			if(me.val >= me.mod)
				do me.val :- me.mod
			end if
			ret me
		end func
		+func sub(a: int): modInt
			if(me.val < a)
				do me.val :+ me.mod
			end if
			do me.val :- a
			ret me
		end func
		+func mul(a: int): modInt
			do me.val :: me.val * a % me.mod
			ret me
		end func
		+func div(a: int): modInt
			do me.val :: me.val * me.modPow(a, me.mod - 2) % me.mod
			ret me
		end func
		+func pow(a: int): modInt
			do me.val :: me.modPow(me.val, a)
			ret me
		end func
		+*func toStr(): []char
			ret "\{me.val}"
		end func
		
		func modPow(a: int, b: int): int
			if(b = 0)
				ret 1
			end if
			var res: int :: me.modPow(a, b / 2)
			do res :: res * res % me.mod
			if(b % 2 = 1)
				do res :: res * a % me.mod
			end if
			ret res
		end func
	end class
end func