#include <iostream>
#include <cstdint>
#include <vector>

static inline constexpr uint_fast32_t check(const uint_fast32_t N, const std::vector<uint_fast32_t>& A, const uint_fast32_t mask) noexcept
{
	uint_fast32_t W = 0, B = 0;
	for (uint_fast32_t i = 0; i != N; ++i)
	{
		if ((A[i] & mask) == A[i]) W |= A[i];
		else if ((A[i] & mask) == 0) B |= A[i];
		else return 0;
	}

	return W * B;
}

static inline constexpr std::pair<uint_fast32_t, std::string> solve(const uint_fast32_t N, const std::vector<uint_fast32_t>& A) noexcept
{
	uint_fast32_t ans = 0, best_mask = 0;
	for (uint_fast32_t i = 0; i != 4096; ++i)
	{
		const uint_fast32_t result = check(N, A, i);
		if (ans < result) ans = result, best_mask = i;
	}

	std::string S;
	S.reserve(N);
	for (uint_fast32_t i = 0; i != N; ++i)
	{
		if ((A[i] & best_mask) == 0) S.push_back('B');
		else S.push_back('W');
	}

	return std::make_pair<uint_fast32_t, std::string>(std::move(ans), std::move(S));
}

static inline void output(const std::pair<uint_fast32_t, std::string>& ans) noexcept
{
	std::cout << ans.first << '\n' << ans.second << '\n';
}

int main()
{
	std::cin.tie(nullptr);
	std::ios::sync_with_stdio(false);

	uint_fast32_t N, i;
	std::cin >> N;
	std::vector<uint_fast32_t> A(N);
	for (i = 0; i != N; ++i)
		std::cin >> A[i];

	output(solve(N, A));
	return 0;
}