#include<bits/stdc++.h>
#define pb push_back
#define pii pair<int,int>
#define MP make_pair
#define fi first
#define se second
using namespace std;
int id[4],v[4];
vector<pii> ans;
void calc(){
	int k=v[2]/v[1],r=v[2]%v[1];
	for(int i=0;v[2]!=r;i++){
		if(k>>i&1) ans.pb(MP(id[2],id[1])),v[2]-=v[1],v[1]*=2;
		else ans.pb(MP(id[3],id[1])),v[3]-=v[1],v[1]*=2;
	}
}
signed main(){
//	freopen("a.in","r",stdin);
//	freopen("a.out","w",stdout);
	ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
	cin>>v[1]>>v[2]>>v[3];
	id[1]=1;id[2]=2;id[3]=3;
	while(true){
		if(v[1]>v[2]) swap(v[1],v[2]),swap(id[1],id[2]);
		if(v[2]>v[3]) swap(v[2],v[3]),swap(id[2],id[3]);
		if(!v[1]) break;
		calc();
	}
	cout<<ans.size()<<'\n';
	for(pii x:ans) cout<<x.fi<<' '<<x.se<<'\n'; 
	return 0;
}