// Source: https://usaco.guide/general/io

#include <bits/stdc++.h>
using namespace std;

#define int int64_t

const int k = 2000000000;

vector<array<int , 3>> e;
vector<vector<array<int , 2>>> g;
vector<int> ans;
vector<int> a;
int u = 0;
int l = 0;

void dfs(int h){
    while(!g[h].empty()){
        if(ans[g[h].back()[1]] != -1){
            g[h].pop_back();
            continue;
        }
        ans[g[h].back()[1]] = 2;
        dfs(g[h].back()[0]);
        ans[g[h].back()[1]] = l;
        l = !l;
    }
}

int32_t main() {
	int n; cin >> n;
    ans.resize(n*2+3 , -1);
    g.resize(n*2+3);
    for(int i = 0; i < n;i++){
        int y , z; cin >> y >> z;
        a.push_back(y);
        a.push_back(z+k);
        e.push_back({y , z+k , u++});
    }
    sort(a.begin() , a.end());
    a.erase(unique(a.begin(),a.end()),a.end());
    for(int i = 0; i < n;i++){
        e[i][0] = lower_bound(a.begin() , a.end() , e[i][0])-a.begin();
        e[i][1] = lower_bound(a.begin() , a.end() , e[i][1])-a.begin();
        g[e[i][0]].push_back({e[i][1] , e[i][2]});
        g[e[i][1]].push_back({e[i][0] , e[i][2]});
    }
    int r = -1;
    for(int i = 0; i < g.size();i++){
        if(g[i].size()%2 == 1){
            if(r == -1){
                r = i;
                continue;
            }
            g[i].push_back({r , u});
            g[r].push_back({i , u++});
            r = -1; 
        }
    }
    for(int i = 0; i < g.size();i++)if(g[i].size() != 0)dfs(i);
    for(int i = 0; i < n;i++){
        if(ans[i]){
            cout << "L";
        }else{
            cout << "F";
        }
    }
}