#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
struct String {
int id, a, b;
};
int main() {
ios::sync_with_stdio(false);
cin.tie(NULL);
int N;
cin >> N;
vector<String> strings(N);
vector<int> count(2 * N, 0);
for (int i = 0; i < N; ++i) {
strings[i].id = i;
cin >> strings[i].a >> strings[i].b;
// A string is "perfect" if (a + b) % 2N == S
int s = (strings[i].a + strings[i].b) % (2 * N);
count[s]++;
}
// Find the symmetry S that requires the fewest moves
int best_s = 0;
for (int s = 0; s < 2 * N; ++s) {
if (count[s] > count[best_s]) {
best_s = s;
}
}
vector<vector<int>> moves;
for (int i = 0; i < N; ++i) {
int u = strings[i].a;
int v = strings[i].b;
int target_v = (best_s - u + 2 * N) % (2 * N);
if (v == target_v) continue;
// If the other end (v) is actually the reflection of a different target pin
// we can check if moving 'u' instead of 'v' is better, but since the
// goal is just ANY minimal K, fixing one end to its target always works.
// Step 1: Move end 'b' to the target of 'a'
moves.push_back({strings[i].id, v, target_v});
}
// Output K
cout << moves.size() << "\n";
for (const auto& m : moves) {
cout << m[0] << " " << m[1] << " " << m[2] << "\n";
}
return 0;
}
