#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
#define rep(i, n) for(int i=0;i<(n);++i)
#define rep1(i, n) for(int i=1;i<=(n);i++)
#define ll long long
using mint = modint998244353;
using P = pair<ll,ll>;
using lb = long double;
using T = tuple<ll, ll, ll>;
#ifdef LOCAL
#  include <debug_print.hpp>
#  define dbg(...) debug_print::multi_print(#__VA_ARGS__, __VA_ARGS__)
#else
#  define dbg(...) (static_cast<void>(0))
#endif

int main()
{
    int n;
    cin >> n;
    vector<int> a(n);
    rep(i,n) {
        cin >> a[i];
    }
    vector<int> dp(1<<12);
    vector<int> val(1<<12);
    dp[0] = 1;
    rep(i,n) {
        vector<int> p(1<<12);
        vector<int> pval(1<<12);
        swap(dp, p);
        swap(val, pval);
        rep(j,1<<12) {
            if(p[j]==0) continue;
            if((j&a[i])==0) {
                dp[j] = 1;
                val[j] = pval[j]|a[i];
            }
            if((pval[j]&a[i])==0) {
                val[j|a[i]] = pval[j];
                dp[j|a[i]] = 1;
            }
        }
    }
    int ans = 0;
    rep(i,1<<12) if(dp[i]) {
        ans = max(ans, i*val[i]);
        // dbg(i,j);
    }
    string fans;
    rep(i,1<<12) if(dp[i] && i*val[i]==ans) {
        rep(k,n) {
            if(a[k]&i) fans+='W';
            else fans+='B';
        }
        cout << ans << endl;
        cout << fans << endl;
        return 0;
    }
    return 0;
}