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

int N, be;
bool nulle[100005];
int beol[100005];
char c;

int main()
{
    cin >> N;

    for(int i = 1; i <= N; i++)
    {
        cin >> c;
        if(c=='R')
        {
            beol[i]=0;
        }
        else
        {
            cin >> be;
            beol[i]=be;
        }
    }
    for(int i = N; i > 0; i--)
    {
        if(nulle[i]==0) //csinal valamit
        {
            nulle[beol[i]]=1;
        }
    }

    vector<int> ans;

    for(int i = 1; i <= N; i++)
    {
        if(nulle[i]==0) ans.push_back(i);
    }
    cout << ans.size() << "\n";
    for(int a:ans) cout << a << " ";cout << "\n";
    return 0;
}