#include <bits/stdc++.h>

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

#pragma GCC optimize("O3")

using namespace std;
using namespace __gnu_pbds;

//#define int long long
#define double long double
#define _ << ' ' <<
#define For(i,z) for(int32_t i=0;i<(z);i++)
#define sqr(a) ((a)*(a))

#define pii pair<int, int>
#define pdd pair<double, double>
#define f first
#define s second

template<typename T>
using orset = tree <T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

template<typename T, typename K>
using ormap = tree <T, K, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

template<typename T, typename K> inline void umax(T &a, K b) { a = max(a, (T)b); }
template<typename T, typename K> inline void umin(T &a, K b) { a = min(a, (T)b); }
mt19937_64 rnd(chrono::steady_clock::now().time_since_epoch().count());

const int32_t N = 1e6+10;
const int64_t INF = 1e15;
const pair<int64_t, int64_t> PINF = make_pair(INF, INF);
const double EPS = 1e-7;
const int64_t MOD1 = 99989;
const int64_t MOD2 = 99991;
const int64_t AMOD = 99194853094755497;
const double PI = 3.14159265359;

pii dp[N][26];

int32_t main() {
    //freopen("input.txt", "r", stdin);
    ios_base::sync_with_stdio(false);
    cin.tie(0); cout.tie(0);

    int k; cin >> k;
    string s;
    s = "a";
    while (k > 0) {
        if (s.back() == 'a')
            s += 'z';
        else
            s += 'a';
        k -= 25;
    }
    For (i, s.size()-1) {
        if (s[i] == 'z') {
            int cc = min((-k)/2, (int)'z' - 'a');
            s[i] -= cc;
            k += cc * 2;
            if (k >= 0) break;
        }
    }
    if (k > 0) {
        if (s.back() == 'z')
            s.back() -= k;
        else
            s.back() += k;
    } else {
        if (s.back() == 'z')
            s.back() += k;
        else
            s.back() -= k;

    }
    cout << s << endl;
}