#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
const int MAXN = 1e5 + 5;

void No(void){ printf("NO\n"); exit(0);}

vector<int> g[MAXN];
int type[MAXN];

int dep[MAXN];
int f[MAXN];
vector<pii> ans;

void dfs_f(int u)
{
	f[u] = 0;
	for(int v: g[u])
	{
		dep[v] = dep[u] + 1;
		dfs_f(v);
	}
	
	auto upd = [&] (int v)
	{
		if(f[u]) No();
		f[u] = v;
	};
	
	{
		vector<int> id;
		for(int v: g[u])
			if(f[v] && type[f[v]] == 2)
				id.emplace_back(f[v]);
		
		if(type[u] == 2)
			id.emplace_back(u);
		
		sort(id.begin(), id.end(), [&] (int x,int y){
			return dep[x] < dep[y];
		});
		
		for(int i=0; i<(int)id.size(); ++i)
		{
			if(i+1<(int)id.size() && dep[id[i]] == dep[id[i+1]])
			{
				ans.emplace_back(id[i], id[i+1]);
				++i;
				continue;
			}
			upd(id[i]);
		}
	}
	
	{
		vector<int> id;
		for(int v: g[u])
			if(f[v] && (type[f[v]] == 0 || type[f[v]] == 1))
				id.emplace_back(f[v]);
		
		if(type[u] == 0 || type[u] == 1)
			id.emplace_back(u);
		
		sort(id.begin(), id.end(), [&] (int x,int y){
			return dep[x] == dep[y]? type[x] < type[y]: dep[x] < dep[y];
		});
		
		stack<int> sta;
		for(int v: id)
		{
			if(type[v] == 0)
			{
				if(sta.size())
				{
					ans.emplace_back(v, sta.top());
					sta.pop();
				}
				else
				{
					upd(v);
				}
			}
			else
			{
				sta.push(v);
			}
		}
		while(sta.size())
			upd(sta.top()), sta.pop();
	}
}

int main(void)
{
	int n;
	scanf("%d",&n);
	for(int k=2; k<=n; ++k)
	{
		static char tmp[100];
		int i,j;
		scanf("%d%d%s",&i,&j,tmp+1);
		g[j].emplace_back(i);
		type[i] = tmp[1] == 'C'? 0: tmp[1] == 'D'? 1: tmp[1] == 'T'? 2: -1;
	}
	
	dfs_f(1);
	
	printf("YES\n");
	for(auto t: ans)
		printf("%d %d\n",t.first,t.second);
	return 0;
}