#include <iostream>
#include <vector>
#include <algorithm>
#include <stack>

using namespace std;

int lastColor = 1;

void DFS(int curr, vector<stack<pair<int, int>>> &sorok, vector<bool> &visited, vector<int> &color)
{
    while(!sorok[curr].empty()){
        pair<int, int> next = sorok[curr].top();
        sorok[curr].pop();
        if(visited[next.second]){
            continue;
        }
        visited[next.second] = true;
        color[next.second] = lastColor;
        lastColor *= -1;
        DFS(next.first, sorok, visited, color);
    }
}

int main()
{
    int N;
    cin >> N;
    vector<pair<int, int>> pontok(N);
    int koordx[N], koordy[N];
    for(int i = 0; i < N; i++){
        cin >> pontok[i].first >> pontok[i].second;
        koordx[i] = pontok[i].first;
        koordy[i] = pontok[i].second;
    }
    sort(koordx, koordx + N);
    sort(koordy, koordy + N);
    vector<stack<pair<int, int>>> sorok(2*N+1);

    for(int i = 0; i < N; i++){
        pontok[i].first = lower_bound(koordx, koordx + N, koordx[i]) - koordx;
        pontok[i].second = lower_bound(koordy, koordy + N, koordy[i]) - koordy + N;
        sorok[pontok[i].first].push({pontok[i].second, i});
        sorok[pontok[i].second].push({pontok[i].first, i});
    }
    vector<bool> visited(N, false);
    vector<int> color{N};

    for(int i = 0; i < N; i++){
        DFS(i, sorok, visited, color);
    }

    for(int i = 0; i < N; i++){
        if(color[i] == 1){
            cout << "F";
        }
        else{
            cout << "L";
        }
    }

    return 0;
}