#include <bits/stdc++.h>
#if defined(LOCAL)
#include "debug.cpp"
#else
#define debug(x...) 0
#endif // LOCAL
using namespace std;
using ll = long long;
#define all(a) (a).begin(), (a).end()
void umax(ll &a, ll b){
a = max(a, b);
}
void solve(){
int n; cin >> n;
vector<int> r(n), c(n);
vector<char> d(n);
vector<int> dead(n);
map<int, set<pair<int, int>>> d1;
set<array<int, 3>> pq;
for(int i=0; i<n; i++){
cin >> r[i] >> c[i] >> d[i];
d1[r[i]+c[i]].insert({r[i], i});
}
for(auto [id, v]:d1){
for(auto it=v.begin(); next(it)!=v.end(); it++){
auto [r1, i1]=*it;
auto [r2, i2]=*next(it);
if(d[i1]!=d[i2]){
pq.insert({abs(r[i1]-r[i2]), i1, i2});
}
}
debug(id, v);
}
auto remove = [&](int i){
dead[i]=1;
auto it = d1[r[i]+c[i]].lower_bound({r[i], i});
int il = -1, ir = -1;
if(next(it)!=d1[r[i]+c[i]].end()){
auto [_, i2] = *next(it);
pq.erase({abs(r[i]-r[i2]), i, i2});
ir=i2;
}
if(it!=d1[r[i]+c[i]].begin()){
auto [_, i2] = *prev(it);
pq.erase({abs(r[i]-r[i2]), i2, i});
il=i2;
}
d1[r[i]+c[i]].erase(it);
if(il!=-1 and ir!=-1){
pq.insert({abs(r[il]-r[ir]), il, ir});
}
};
while(pq.size()){
debug(pq);
vector<array<int, 3>> cur = {*pq.begin()};
pq.erase(pq.begin());
while(pq.size() and pq.begin()->front() == cur.front().front()){
cur.push_back(*pq.begin());
pq.erase(pq.begin());
}
debug(cur);
// remove all ships that colide
for(auto [t, i1, i2]:cur){
debug(t, i1, i2);
remove(i1);
remove(i2);
}
}
debug(dead);
for(int i=0; i<n; i++){
if(dead[i]) continue;
cout << i + 1<< endl;
}
}
int main(){
solve();
return 0;
}
