#include <bits/stdc++.h>
using namespace std;
const int c=8e5+5;

vector<int> compx;
vector<int> compy;

int fx(int k){
    return lower_bound(compx.begin(),compx.end(),k)-compx.begin() + 1;
}

int fy(int k){
    return lower_bound(compy.begin(),compy.end(),k)-compy.begin() + 1 + compx.size();
}

int n,N;
vector<pair<int,int>> adj[c];
bool volt[c];
int idx[c];
bool ans[c], vis[c], deg[c];
vector<pair<int,int>> edg;

void dfs(int v){
    vis[v]=1;
    while(idx[v]<adj[v].size()){
        int x=idx[v];
        int id=adj[v][x].second;
        if(volt[id]){
            ++idx[v];
            continue;
        }
        volt[id]=1;
        ++idx[v];
        if(v<=compx.size()) ans[id]=1;
        else ans[id]=0;
        dfs(adj[v][x].first);
    }
}


int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    cin>>n;
    for(int i=1;i<=n;i++){
        int a,b; cin>>a>>b;
        edg.push_back(make_pair(a,b));
        compx.push_back(a);
        compy.push_back(b);
    }

    sort(compx.begin(),compx.end());
    compx.resize(unique(compx.begin(),compx.end())-compx.begin());

    sort(compy.begin(),compy.end());
    compy.resize(unique(compy.begin(),compy.end())-compy.begin());

    N=compx.size()+compy.size();

    for(int i=0;i<n;i++){
        int a=fx(edg[i].first);
        int b=fy(edg[i].second);
        adj[a].push_back(make_pair(b,i));
        adj[b].push_back(make_pair(a,i));
        deg[a]^=1; deg[b]^=1;
    }

    int m=n;
    int p=-1;
    for(int i=1;i<=N;i++){
        if(deg[i]){
            if(p==-1) p=i;
            else{
                adj[i].push_back(make_pair(p,m));
                adj[p].push_back(make_pair(i,m++));
                p=-1;
            }
        }
    }

    for(int i=1;i<=N;i++){
        if(!vis[i]) dfs(i);
    }

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