#if !defined(__clang__) && defined(__GNUC__)
#include <bits/stdc++.h>
#else
#include <cstdlib>
#include <climits>
#include <iostream>
#include <cstdint>
#include <vector>
#include <string>
#include <complex>
#include <bitset>
#include <queue>
#include <deque>
#include <stack>
#include <utility>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <regex>
#endif //  !defined(__clang__) && defined(__GNUG__)
#include <boost/lexical_cast.hpp>
#include <boost/algorithm/string.hpp>
#include <boost/multi_array.hpp>
#include <boost/optional.hpp>
#include <boost/math/common_factor_rt.hpp>

using namespace std;

int main()
{
    int64_t N;
    std::cin >> N;

    /*
      1: 2
      7: 3
      4: 4
      2: 5
      3: 5
      5: 5
      0: 6
      6: 6
      9: 6
      8: 7
    */

    if (N == 3) {
        std::cout << 7 << std::endl;
        return 0;
    }

    int64_t ans = 1;
    N -= 2;
    while (N >=2) {
        ans *= 10;
        ans += 1;
        N -= 2;
    }

    std::cout << ans << std::endl;

    return 0;
}