#include <iostream>
#include <algorithm>
#include <iomanip>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <numeric>
#include <bitset>
#include <cmath>

static const int MOD = 1000000007;
using ll = long long;
using u32 = uint32_t;
using namespace std;

template<class T> constexpr T INF = ::numeric_limits<T>::max() / 32 * 15 + 208;

int main() {
    int n;
    cin >> n;
    string ans;
    char a = 'a', b = 'b';
    while(n){
        int cnt = 2;
        while(cnt/2 <= n){
            n -= cnt/2;
            ans += (cnt&1 ? a : b);
            cnt++;
        }
        a += 2; b += 2;
    }
    cout << ans << "\n";
    return 0;
}