#include "gift.h"
#include <bits/stdc++.h>
using namespace std;
const int nx=5e5+5;
int qs[nx], lst;
string s;
vector<pair<int, int>> rng;
int construct(int n, int r, std::vector<int> a, std::vector<int> b, std::vector<int> x) {
for (int i=0; i<r; i++) if (x[i]==1) qs[a[i]]++, qs[b[i]]--;
for (int i=0; i<n; i++)
{
qs[i+1]+=qs[i];
if (!qs[i]) rng.push_back({lst, i}), lst=i+1;
}
for (int i=0; i<r; i++)
{
if (x[i]==2)
{
auto itr=upper_bound(rng.begin(), rng.end(), make_pair(b[i], INT_MAX));
if (prev(itr)->first<=a[i]) return 0;
}
}
s.resize(n, 'R');
for (int i=0; i<rng.size(); i+=2) for (int j=rng[i].first; j<=rng[i].second; j++) s[j]='B';
craft(s);
return 1;
}
