#include <iostream>
#include <vector>
#include <algorithm>
#include <map>
#include <stack>
#include <deque>
#include <string>
using namespace std;
void var(int c, int f, pair<int, int>& v1, pair<int, int>& v2) {
    if (c == 1) v1 = pair<int, int>(2, 3);
    if (c == 2) v1 = pair<int, int>(1, 3);
    if (c == 3) v1 = pair<int, int>(2, 1);
    if (f == 1) v2 = pair<int, int>(2, 3);
    if (f == 2) v2 = pair<int, int>(1, 3);
    if (f == 3) v2 = pair<int, int>(2, 1);

}
int main()
{
    int n;
    cin >> n;
    vector<int> ans;
    map<int, vector<int>> cards;
    int c, f;
    cin >> c >> f;
    cards[3 * (c - 1) + f].push_back(1);
    for (int i = 2; i <= n; i++) {
        cin >> c >> f;
        if (cards[3 * (c - 1) + f].size() == 2) {
            ans.push_back(i);
            ans.push_back(cards[3 * (c - 1) + f][0]);
            ans.push_back(cards[3 * (c - 1) + f][1]);
            cards[3 * (c - 1) + f].pop_back();
            cards[3 * (c - 1) + f].pop_back();
        }
        else {
            pair<int, int> v1;
            pair<int, int> v2;
            var(c, f, v1, v2);
            if (cards[3 * (c - 1) + v2.first].size() > 0 & cards[3 * (c - 1) + v2.second].size() > 0) {
                ans.push_back(i);
                ans.push_back(cards[3 * (c - 1) + v2.first].back());
                ans.push_back(cards[3 * (c - 1) + v2.second].back());
                cards[3 * (c - 1) + v2.first].pop_back();
                cards[3 * (c - 1) + v2.second].pop_back();

            }
            else if(cards[3 * (v1.first - 1) + f].size() > 0 & cards[3 * (v1.second - 1) + f].size() > 0){
                ans.push_back(i);
                ans.push_back(cards[3 * (v1.first - 1) + f].back());
                ans.push_back(cards[3 * (v1.second - 1) + f].back());
                cards[3 * (v1.first - 1) + f].pop_back();
                cards[3 * (v1.second - 1) + f].pop_back();

            }
            else if(cards[3 * (v1.first - 1) + v2.first].size() > 0 & cards[3 * (v1.second - 1) + v2.second].size() > 0){
                ans.push_back(i);
                ans.push_back(cards[3 * (v1.first - 1) + v2.first].back());
                ans.push_back(cards[3 * (v1.second - 1) + v2.second].back());
                cards[3 * (v1.first - 1) + v2.first].pop_back();
                cards[3 * (v1.second - 1) + v2.second].pop_back();

            }
            else if(cards[3 * (v1.first - 1) + v2.second].size() > 0 & cards[3 * (v1.second - 1) + v2.first].size() > 0){
                ans.push_back(i);
                ans.push_back(cards[3 * (v1.first - 1) + v2.second].back());
                ans.push_back(cards[3 * (v2.second - 1) + v2.first].back());
                cards[3 * (v1.first - 1) + v2.second].pop_back();
                cards[3 * (v2.second - 1) + v2.first].pop_back();

            }
            else cards[3 * (c - 1) + f].push_back(i);


        }
    }
    for (int i = 0; i < ans.size() - 2;i+=3) cout << ans[i] << " " << ans[i + 1] << " " << ans[i + 2] << endl;


}