import std.conv, std.functional, std.range, std.stdio, std.string;
import std.algorithm, std.array, std.bigint, std.complex, std.container, std.math, std.numeric, std.regex, std.typecons;
import core.bitop;

class EOFException : Throwable { this() { super("EOF"); } }
string[] tokens;
string readToken() { for (; tokens.empty; ) { if (stdin.eof) { throw new EOFException; } tokens = readln.split; } auto token = tokens.front; tokens.popFront; return token; }
int readInt() { return readToken.to!int; }
long readLong() { return readToken.to!long; }
real readReal() { return readToken.to!real; }

bool chmin(T)(ref T t, in T f) { if (t > f) { t = f; return true; } else { return false; } }
bool chmax(T)(ref T t, in T f) { if (t < f) { t = f; return true; } else { return false; } }

int binarySearch(alias pred, T)(in T[] as) { int lo = -1, hi = cast(int)(as.length); for (; lo + 1 < hi; ) { const mid = (lo + hi) >> 1; (unaryFun!pred(as[mid]) ? hi : lo) = mid; } return hi; }
int lowerBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a >= val)); }
int upperBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a > val)); }


int[] getZ(T)(T a) {
  const n = cast(int)(a.length);
  auto z = new int[n + 1];
  int j = 0;
  foreach (i; 1 .. n) {
    if (i + z[i - j] < j + z[j]) {
      z[i] = z[i - j];
    } else {
      int k = max(j + z[j] - i, 0);
      for (; i + k < n && a[k] == a[i + k]; ++k) {}
      z[i] = k;
      j = i;
    }
  }
  z[0] = n;
  return z;
}

long solve(in string s) {
  const n = cast(int)(s.length);
  auto dp = new long[n + 1];
  foreach_reverse (i; 0 .. n + 1) {
    if (i <= n - i) {
      const z = getZ(s[i .. n - i]);
      dp[i] = 1;
      foreach (k; 1 .. (n - i - i) / 2 + 1) {
        if (z[n - i - i - k] == k) {
          dp[i] += dp[i + k];
        }
      }
    }
  }
  return dp[0];
}


void main() {
  debug {
    foreach (s; [
      "aza",
      "aazaa",
      "baazaab",
      "bbaazaabb",
      "accbbaazaabbcca",
    ]) {
      writeln(solve(s), " ", s);
    }
  }
  
  try {
    for (; ; ) {
      const N = readLong();
      string ans = "z";
      char c = 'a';
      foreach_reverse (i; 0 .. bsr(N)) {
        ans = c ~ ans ~ c;
        if ((N >> i) & 1) {
          ++c;
          if (c == 'z') {
            c = 'a';
          }
          ans = c ~ ans ~ c;
        }
      }
      debug {
        writeln(N, " ", solve(ans));
      }
      writeln(ans);
    }
  } catch (EOFException e) {
  }
}