//Rahman ve Rahim olan Allah'ın adıyla
#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
#define int long long
#define pb push_back
#define fi first
#define se second
#define mid (st+end)/2
using namespace std;
vector<int>bounds(1);
int32_t main(){
ios_base::sync_with_stdio(false);cin.tie(0);
int n;cin>>n;vector<array<int,2>>arr(n);vector<int>res(n*2,0);
vector<int>adj(2*n);vector<bool>vis(n);
for(int i=0;i<n;i++){
cin>>arr[i][0]>>arr[i][1];res[(arr[i][0]+arr[i][1])%(2*n)]++;adj[arr[i][0]]=i;adj[arr[i][1]]=i;
}int mx=0,mxi=0;for(int i=1;i<n*2;i+=2){
if(res[i]>mx){mx=res[i];mxi=i;}
}cout<<n-mx<<"\n";
for(int i=0;i<n;i++){if((arr[i][0]+arr[i][1]+(n*2))%(n*2)==mxi){vis[i]=true;}}
for(int i=0;i<n;i++){
if(vis[i]) continue;
cout<<i<<" "<<arr[i][1]<<" "<<(mxi-arr[i][0]+(n*2))%(n*2)<<"\n";int nd=(mxi-arr[i][0]+(n*2))%(n*2);vis[i]=true;
while(vis[adj[nd]]==false){if(arr[adj[nd]][0]==nd) swap(arr[adj[nd]][0],arr[adj[nd]][1]);
cout<<adj[nd]<<" "<<arr[adj[nd]][1]<<" "<<(mxi-arr[adj[nd]][0]+(n*2))%(n*2)<<"\n";vis[adj[nd]]=true;nd=(mxi-arr[adj[nd]][0]+(n*2))%(n*2);
}
}
}
