//(ᗜ ˰ ᗜ)
// #define NDEBUG
#include <bits/stdc++.h>
using namespace std;
namespace LING
{
#ifdef ONLINE_JUDGE
#define DBG(...) ;
#define dbg(...) ;
#else
#define DBG(x) cout << "! " << #x << " = " << x << endl
#include "debug.h"
#endif
    using ll = long long;
    using db = double;
#define SPO(x) fixed << setprecision(x)
#define FOR(i, l, r) for (ll i = l; i <= (r); ++i)
#define ROF(i, r, l) for (ll i = r; i >= (l); --i)
#define edl '\n'
#define fir first
#define sec second
#define str string
#define pll pair<ll, ll>
#define heap priority_queue
    // constexpr db PI = acos(-1.0);
    // constexpr db EPS = 1.0e-9;
    constexpr long long LNF = 0x3f3f3f3f3f3f3f3fLL;
    constexpr int INF = 0x3f3f3f3f;
    constexpr long long MOD = 998244353;
    constexpr ll MXN = 1e6 + 5;
    ll KSM(ll base, ll exp, ll MOD)
    {
        ll res = 1;
        base %= MOD;
        while (exp)
        {
            if (exp & 1)
                res = (res * base) % MOD;
            base = (base * base) % MOD;
            exp >>= 1;
        }
        return res;
    }
}
using namespace LING;
ll n;
ll a[MXN];
ll d[MXN];
vector<ll> g[MXN];
void dfs(ll u, ll fa)
{
    d[u] = d[fa] + 1;
    for (auto &v : g[u])
    {
        if (v == fa)
            continue;
        dfs(v, u);
    }
}
void Solve(void)
{
    cin >> n;
    FOR(i, 2, n)
    {
        ll u, v, w;
        str t;
        cin >> u >> v >> t;
        if (t == "Chang")
            w = 1;
        else if (t == "Duan")
            w = 2;
        else if (t == "Tong")
            w = 3;
        else
            w = 0;
        a[u] = w;
        g[u].push_back(v);
        g[v].push_back(u);
    }
    dfs(1, 0);
    vector<pll> chang, duan, tong;
    FOR(i, 1, n)
    {
        if (a[i] == 1)
            chang.push_back({d[i], i});
        else if (a[i] == 2)
            duan.push_back({d[i], i});
        else if (a[i] == 3)
            tong.push_back({d[i], i});
    }
    if (tong.size() % 2 || chang.size() != duan.size())
    {
        cout << "NO" << edl;
        return;
    }
    sort(chang.begin(), chang.end());
    sort(duan.begin(), duan.end());
    sort(tong.begin(), tong.end());

    vector<pll> ans;
    FOR(i, 0, tong.size() - 1)
    {
        if (tong[i].first != tong[i + 1].first)
        {
            cout << "NO" << edl;
            return;
        }
        else
            ans.push_back({tong[i].second, tong[i + 1].second});
        ++i;
    }
    FOR(i, 0, duan.size() - 1)
    {
        if (duan[i].first >= chang[i].first)
        {
            cout << "NO" << edl;
            return;
        }
        else
            ans.push_back({duan[i].second, chang[i].second});
    }
    cout << "YES" << edl;
    for (auto &i : ans)
        cout << i.first << " " << i.second << edl;
    return;
}
int main(void)
{
    ios::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
    // #ifndef ONLINE_JUDGE
    // freopen("cin.txt","r",stdin);
    // freopen("cout.txt","w",stdout);
    // #endif

    int t = 1;
    // cin >> t;
    while (t--)
        Solve();
    return 0;
}