#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
using namespace std;
using namespace __gnu_pbds;
template <typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template <typename T>
using ordered_multiset = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update>;
#define int long long
#define Shahriyor ios::sync_with_stdio(false), cin.tie(0), cout.tie(0)
#define vi vector<int>
#define vvi vector<vi>
#define vvvi vector<vvi>
#define vc vector<char>
#define vs vector<string>
#define vp vector<pair<int,int>>
#define vvp vector<vector<pair<int,int>>>
#define all(x) (x).begin(), (x).end()
#define allr(x) x.rbegin(), x.rend()
#define sz(x) (int)x.size()
#define endl '\n'
#define len(a) (int)(a).length()
#define inf 4e18
#define print(x) { cout << x << endl; return; }
void Solve();
int mod = 1e9+7;
int LOG = 20;
vi dx = {-1, 1, 0, 0, 1, -1, 1, -1};
vi dy = {0, 0, 1, -1, 1, -1, -1, 1};
ostream& operator<<(ostream& out, vi& a) {
for(int i=0;i<sz(a);i++) out << a[i] << ' ';
return out;
}
istream& operator>>(istream& in, vi& a) {
for(int i=0;i<sz(a);i++) in >> a[i];
return in;
}
int sum(vi& l) {return accumulate(all(l),(int)0);}
int binpow(int a, int b){
int res = 1;
while(b){
if(b & 1) res = res * a % mod;
a = a * a % mod;
b >>= 1;
}
return res;
}
signed main(){
clock_t start = clock();
Shahriyor;
int t = 1;
// cin >> t;
while(t--) Solve();
// cerr << "Time: " << double(clock() - start) / double(CLOCKS_PER_SEC) * 1000 << " ms\n";
}
void Solve(){
int n; cin >> n;
vector<pair<int,int>> cur(n);
vector<int> cnt(2*n, 0);
for(int i = 0; i < n; i++){
cin >> cur[i].first >> cur[i].second;
cnt[(cur[i].first + cur[i].second) % (2*n)]++;
}
// choose best target (only odd ones)
int mx = 0, t = -1;
for(int i = 1; i < 2*n; i += 2){
if(cnt[i] > mx){
mx = cnt[i];
t = i;
}
}
// edge case: no odd rotation present
if(t == -1){
t = 1;
mx = 0;
}
cout << n - mx << endl;
// pin -> string mapping
vector<int> pin_to_string(2*n, -1);
for(int i = 0; i < n; i++){
pin_to_string[cur[i].first] = i;
pin_to_string[cur[i].second] = i;
}
vector<int> good(n, 0);
for(int i = 0; i < n; i++){
if((cur[i].first + cur[i].second) % (2*n) == t){
good[i] = 1;
}
}
vector<array<int,3>> ops;
for(int i = 0; i < n; i++){
if(good[i]) continue;
int p = i;
while(true){
int a = cur[p].first;
int b = cur[p].second;
int need = (t - a + 2*n) % (2*n);
if(need == b){
good[p] = 1;
break;
}
int q = pin_to_string[need];
// move b -> need
ops.push_back({p, b, need});
// update pin ownership
pin_to_string[b] = -1;
pin_to_string[need] = p;
// update string
if(cur[p].first == b) cur[p].first = need;
else cur[p].second = need;
good[p] = 1;
if(q == p || good[q]) break;
p = q;
}
}
for(auto &op : ops){
cout << op[0] << " " << op[1] << " " << op[2] << endl;
}
}
// Code once, never "guess", have clear plan.
