#include <stdio.h>
#include <atcoder/all>
#include <bits/stdc++.h>
using namespace std;
using namespace atcoder;
using mint = modint998244353;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf32 1000000005
#define Inf64 1000000000000000001LL

int main(){
	
	int n;
	cin>>n;
	vector<int> a(n);
	rep(i,n)cin>>a[i];
	int mb = 0,ans = -1;
	rep(i,4096){
		int b = 0,w = 0;
		rep(j,n){
			if((a[j]&i)==a[j])b |= a[j];
			else w |= a[j];
		}
		if((b&w)!=0)continue;
		if(b!=i)continue;
		if(b*w > ans){
			ans = b*w;
			mb = i;
		}
			
	}
	string anss(n,'a');
	rep(i,n){
		if((a[i]&mb))anss[i] = 'B';
		else anss[i] = 'W';
	}
	cout<<ans<<endl;
	cout<<anss<<endl;
	return 0;
}