#include <iostream>
#include <string>
#include <vector>
#include <cmath>
#include <algorithm>
#include <cstdlib>
#include <ctime>
#include <cstdio>
#include <functional>
#include <set>

using namespace std;

int main()
{	
	int n,nn;
	cin>>n;

	unsigned long long res=0,res2=0;
	if(n==3) res=7;
	else{
		nn=n;
		while(nn>=2){res*=10;res+=1; nn-=2;}

		nn=n;
		while(nn>=3){res2*=10;res2+=7; nn-=3;}
		while(nn>=2){res2*=10;res2+=1; nn-=2;}
		res=max(res,res2);

		nn=n; res2=0;
		while(nn>=6){res2*=10;res2+=9; nn-=6;}
		while(nn>=3){res2*=10;res2+=7; nn-=3;}
		while(nn>=2){res2*=10;res2+=1; nn-=2;}
		res=max(res,res2);

		nn=n; res2=0;
		while(nn>=6){res2*=10;res2+=9; nn-=6;}
		while(nn>=2){res2*=10;res2+=1; nn-=2;}
		res=max(res,res2);

	}

	cout<<res<<endl;

	return 0;

}