#include <bits/stdc++.h>

using namespace std;
using ll = long long;

const int MAXN = 300'001;

bool vis[MAXN];
int vx[MAXN], vy[MAXN];
vector<pair<int, int>> g[MAXN];
int ans[MAXN];

void dfs(int u, int d = 0) {
    while (!g[u].empty()) {
        auto [v, idx] = g[u].back();
        g[u].pop_back();
        if (vis[idx]) continue;
        vis[idx] = true;
        ans[idx] = d;
        dfs(v, d^1);
        return;
    }
}

int main() {
    ios::sync_with_stdio(0); cin.tie(0);
    int n; cin >> n;
    vector<int> comp1, comp2;
    for (int i = 1; i <= n; i++) {
        cin >> vx[i] >> vy[i];
        comp1.emplace_back(vx[i]);
        comp2.emplace_back(vy[i]);
    }
    sort(comp1.begin(), comp1.end());
    sort(comp2.begin(), comp2.end());
    comp1.erase(unique(comp1.begin(), comp1.end()), comp1.end());
    comp2.erase(unique(comp2.begin(), comp2.end()), comp2.end());
    for (int i = 1; i <= n; i++) {
        vx[i] = lower_bound(comp1.begin(), comp1.end(), vx[i])-comp1.begin();
        vy[i] = lower_bound(comp2.begin(), comp2.end(), vy[i])-comp2.begin(); 
        g[vx[i]].emplace_back(vy[i]+n, i);
        g[vy[i]+n].emplace_back(vx[i], i);
    }

    for (int i = 0; i < n; i++) {
        int d = 0;
        while (!g[i].empty()) {
            dfs(i, d);
            d^=1;
        }
    }
    
    for (int i = 1; i <= n; i++) cout << (ans[i]?'F':'L');
    cout << "\n";
    return 0;
}