#include <bits/stdc++.h>

using namespace std;

typedef pair<int, int> pii;

vector<bool> bejart;
vector<queue<pii>> csucsok;
vector<bool> ans;

void dfs(int akt, bool fiu){
    while(!csucsok[akt].empty()){
        pii kovi = csucsok[akt].front();
        csucsok[akt].pop();

        if(bejart[kovi.second]) continue;

        bejart[kovi.second] = 1;
        ans[kovi.second] = fiu;
        dfs(kovi.first, !fiu);
        return;
    }
}

int main(){
    int n;
    cin >> n;

    vector<pii> pontok(n);
    vector<int> pontX(n);
    vector<int> pontY(n);
    for(int i = 0; i < n; i++){
        cin >> pontok[i].first >> pontok[i].second;

        pontX[i] = pontok[i].first;
        pontY[i] = pontok[i].second;
    }

    sort(pontX.begin(), pontX.end());
    sort(pontY.begin(), pontY.end());

    pontX.erase(unique(pontX.begin(), pontX.end()), pontX.end());
    pontY.erase(unique(pontY.begin(), pontY.end()), pontY.end());

    csucsok.assign(3 * n, queue<pii>());
    for(int i = 0; i < n; i++){
        pontok[i].first = lower_bound(pontX.begin(), pontX.end(), pontok[i].first) - pontX.begin();
        pontok[i].second = lower_bound(pontY.begin(), pontY.end(), pontok[i].second) - pontY.begin();

        csucsok[pontok[i].first].push({pontok[i].second + n, i});
        csucsok[pontok[i].second + n].push({pontok[i].first, i});
    }

    /*for(int i = 0; i < n; i++){
        cout << pontok[i].first << " " << pontok[i].second << "\n";
    }*/

    bejart.assign(n, 0);
    ans.assign(n, 0);

    for(int i = 0; i < n; i++){
        bool fiu = 0;
        while(!csucsok[i].empty()){
            dfs(i, fiu);
            fiu = !fiu;
        }
    }

    for(bool x : ans){
        cout << (x ? "F" : "L");
    }
    cout << "\n";
}