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

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

    int N; cin >> N;
    vector<int> A(N);
    for(auto &a : A) cin >> a;

    int n = 12,n2 = 1<<n;
    int answer = 0;
    string s(N,'B');
    for(int i=0; i<n2; i++){
        int W = i,B = (n2-1)-W;
        int x = 0,y = 0;
        for(auto a : A){
            if((W&a) == a) x |= a;
            else if((B&a) == a) y |= a;
            else{x = 0; break;}
        }  
        if(answer < x*y){
            answer = x*y;
            for(int k=0; k<N; k++){
                int a = A.at(k);
                if((W&a) == a) s.at(k) = 'W';
                else s.at(k) = 'B';
            }
        }
    }
    cout << answer << endl;
    cout << s << endl;
}