//Author: Kevin
#include<bits/stdc++.h>
//#pragma GCC optimize("O2")
using namespace std;
#define ll long long
#define ull unsigned ll
#define pb emplace_back
#define mp make_pair
#define ALL(x) (x).begin(),(x).end()
#define rALL(x) (x).rbegin(),(x).rend()
#define srt(x) sort(ALL(x))
#define rev(x) reverse(ALL(x))
#define rsrt(x) sort(rALL(x))
#define sz(x) (int)(x.size())
#define inf 0x3f3f3f3f
#define pii pair<int,int>
#define lb(v,x) (int)(lower_bound(ALL(v),x)-v.begin())
#define ub(v,x) (int)(upper_bound(ALL(v),x)-v.begin())
#define uni(v) v.resize(unique(ALL(v))-v.begin())
#define longer __int128_t
void die(string S){puts(S.c_str());exit(0);}
int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	int n,a,b;
	cin>>n>>a>>b;
	if(n==1)
	{
		cout<<(a==b)<<endl;
		cout<<a<<":"<<b<<endl;
	}
	else
	{
		cout<<max(0,n-a-b)<<endl;
		if(a>=n)
		{
			for(int i=1;i<=n-2;i++)
				cout<<"1:0"<<endl;
			a-=(n-2);
			cout<<a<<":0"<<endl;
			cout<<"0:"<<b<<endl;
		}
		else if(a+b>=n)
		{
			for(int i=1;i<=a;i++)
				cout<<"1:0"<<endl;
			for(int i=a+1;i<n;i++)
				cout<<"0:1"<<endl;
			cout<<"0:"<<b-(n-a-1)<<endl;
		}
		else
		{
			for(int i=1;i<=a;i++)
				cout<<"1:0"<<endl;
			for(int i=1;i<=b;i++)
				cout<<"0:1"<<endl;
			for(int i=1;i<=n-a-b;i++)
				cout<<"0:0"<<endl;
		}
	}
	return 0;
}