#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n;
    cin >> n;
    vector<int> a(n);
    for(auto &&v : a) cin >> v;

    int U = 4096 - 1;
    tuple<int,int,int> mx = {-1, -1, -1};
    for(int S = 0; S < 4096; S++){
        int T = S ^ U;
        bool flg = true;
        int B0 = 0, B1 = 0;
        for(auto v : a){
            if(((S & v) == v)){
                B0 |= v;
                continue;
            }
            if((T & v) == v){
                B1 |= v;
                continue;
            }
            flg = false;
            break;
        }
        if(!flg) continue;
        mx = max(mx, make_tuple(B0 * B1, B0, B1));
    }
    auto [M, S0, S1] = mx;
    cout << M << '\n';
    for(int i = 0; i < n; i++){
        cout << ((S0 & a[i]) == a[i] ? 'B' : 'W'); 
    }
    cout << '\n';
}