#include<bits/stdc++.h> using namespace std; #pragma GCC optimize("O3","unroll-loops") #pragma GCC target("avx,bmi,bmi2,lzcnt,popcnt") // PBDS Template //#include <ext/pb_ds/assoc_container.hpp> //#include <ext/pb_ds/tree_policy.hpp> //using namespace __gnu_pbds; //template <class T> //using ordered_set = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>; //using ordered_multiset = tree<T, null_type, less_equal<T>, rb_tree_tag,tree_order_statistics_node_update>; // Preset const int maxn = 200000; const int INF = 2e9; const long long int LINF = 1e18; const long long int mod = 1e9 + 7; const long long int mod2 = 998244353; const double e = 2.71828; const double PI = acos(-1); const double eps = 1e-10; #define pb push_back #define ll long long //#define int long long #define ull unsigned long long #define ld double #define all(x) x.begin(), x.end() typedef pair<char,char> pc; typedef pair<double,double> pdb; typedef pair<int,int> pi; typedef pair<ll,ll> pll; typedef pair<pi,int> pii; typedef pair<int,ll> pil; typedef pair<ll,int> pli; typedef pair<string,int> psi; typedef pair<int,string> pis; typedef pair<char,int> pci; typedef pair<int,char> pic; typedef pair<int,double> pid; typedef pair<double,int> pdi; int dr[4] = {0,1,0,-1}, dc[4] = {1,0,-1,0}; void solve() { int n,m; cin >> n >> m; pi p[n+m+5]; for (int i=1; i<=n; i++) { cin >> p[i].first; p[i].second = 0; } for (int i=n+1; i<=n+m; i++) { cin >> p[i].first; p[i].second = 1; } sort(p+1,p+n+m+1); // for (int i=1; i<=n+m; i++) cout << p[i].first << ' ' << p[i].second << '\n'; int l = 0, r = 1e9, ans = INF; string res = ""; while (l<=r) { int mid = l + (r-l)/2; // cout << "mid = " << mid << '\n'; stack<int> st; int far = 0; string cfg = ""; for (int i=1; i<=n+m; i++) { int cur = p[i].first; // cout << i << ' ' << cur << ' ' << far << '\n'; // stack<int> temp = st; // cout << "isi stack ="; // while (!temp.empty()) { // cout << ' ' << temp.top(); // temp.pop(); // } // cout << '\n'; if (p[i].second == 0) { if (!st.empty()) { while (!st.empty()) { int top = st.top(); if (p[top].first+mid >= cur) st.pop(); else break; } cfg.pb('L'); } else { far = max(far, cur+mid); cfg.pb('R'); } } else { if (far < cur) st.push(i); } } if (st.empty()) { ans = min(ans, mid); res = cfg; r = mid-1; } else l = mid+1; } if (ans == INF) cout << -1 << '\n'; else { cout << ans << '\n'; cout << res << '\n'; } } int main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); // precompute(); // FFT::init_fft(); int tc = 1; // cin >> tc; // getchar(); // int idx = 1; while (tc--) solve(); return 0; }