#include<gift.h>
#include<bits/stdc++.h>
using namespace std;
int construct(int n, int r, vector<int> a, vector<int> b, vector<int> x) {
int union_find[n];
for (int i = 0; i < n; i++) {
union_find[i] = i;
}
vector<pair<int, int>> one_requirements {};
vector<pair<int, int>> two_requirements {};
for (int i= 0; i < r; i++) {
if (x[i] == 1) {
one_requirements.push_back({a[i], b[i]});
}
else {
two_requirements.push_back({a[i], b[i]});
}
}
sort(one_requirements.begin(), one_requirements.end());
for (auto t : one_requirements) {
int f = t.first;
int g = t.second;
for (int j = f+1; j <= g; j++) {
union_find[j] = union_find[f];
}
}
for (auto t : two_requirements) {
int f = t.first;
int g = t.second;
if (union_find[f] == union_find[g]) return 0;
}
string s = "R";
bool red = true;
for (int i = 1; i < n; i++) {
if (union_find[i] != union_find[i-1]) red = !red;
if (red) s += 'R';
else s += 'B';
}
craft(s);
return 1;
}
