#ifndef ONLINE_JUDGE
#define _GLIBCXX_DEBUG
#endif
#include <bits/stdc++.h>
#include <cassert>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
using mint = modint998244353;
//using mint = modint1000000007;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define repu(i, s, t) for (int i = (int)(s); i < (int)(t); i++)
#define repd(i, s, t) for (int i = (int)(s)-1; i >= (int)(t); i--)
#define all(v) v.begin(), v.end()
void _u() { cerr << endl; } template <class H, class... T> void _u(H&& h, T&&... t) { cerr << h << ", "; _u(move(t)...); }
#define U(...) { cerr << #__VA_ARGS__ << ": "; _u(__VA_ARGS__); }
template<typename T> bool chmax(T &a, const T b) { if(a >= b) return false; a = b; return true; }
template<typename T> bool chmin(T &a, const T b) { if(a <= b) return false; a = b; return true; }
template<typename T> istream& operator>>(istream &in, vector<T> &a) { for(T &x: a) in >> x; return in; }
template<typename T> ostream& operator<<(ostream &out, const vector<T> &a) { for(const T &x: a) out << x << ' '; return out; }
const int di[] = {1, 0, -1, 0, 1, 1, -1, -1, 0};
const int dj[] = {0, 1, 0, -1, -1, 1, 1, -1, 0};


int main() {
    int n;
    cin >> n;
    vector<int> a(n);
    cin >> a;

    int res = -1;
    string ans;
    rep(wi, 1<<12) {
        string col(n, ' ');
        rep(i, n) {
            bool b = true;
            rep(j, 12) {
                if((wi>>j&1) && (a[i]>>j&1)) b = false;
            }
            if(b) col[i] = 'B';
            else col[i] = 'W';
        }
        int wr = 0, br = 0;
        rep(i, n) {
            if(col[i] == 'W') wr |= a[i];
            else br |= a[i];
        }
        if((wr & br) != 0) continue;
        int wb = wr * br;
        if(chmax(res, wb)) ans = col;
    }
    cout << res << endl;
    cout << ans << endl;
    return 0;
}