#include <bits/stdc++.h>
#pragma GCC optimize(3, "Ofast", "inline")
using namespace std;
const int N = 1e5 + 5;
const int M = 1e6 + 5;
const int MOD = 1e9 + 7;
const int CM = 998244353;
const int INF = 0x3f3f3f3f;
const double eps = 1e-6;
template <typename T>
T MAX(T a, T b) {
  return a > b ? a : b;
}
template <typename T>
T MIN(T a, T b) {
  return a > b ? b : a;
}
template <typename T>
T GCD(T a, T b) {
  return b == 0 ? a : GCD(b, a % b);
}
template <typename T>
T LCM(T a, T b) {
  return a / GCD(a, b) * b;
}
template <typename T>
T ABS(T a) {
  return a > 0 ? a : -a;
}
template <typename T>
T ADD(T a, T b, T MOD) {
  return (a + b) % MOD;
}
template <typename T>
T DEL(T a, T b, T MOD) {
  return ((a - b) % MOD + MOD) % MOD;
}
template <typename T>
T getmod(T a, T mod) {
  return (a % mod + mod) % mod;
}
template <typename T>
void debug(T a, char x) {
  return;
}
int rand(int a, int b) { return rand() % (b - a + 1) + a; }
string a, b;
bool divi(string a, string b) {
  if (a == b) return 1;
  int n = a.length();
  if (n & 1) return 0;
  string a1 = a.substr(0, n / 2), a2 = a.substr(n / 2, n / 2);
  string b1 = b.substr(0, n / 2), b2 = b.substr(n / 2, n / 2);
  if (divi(a1, b2) && divi(a2, b1)) return 1;
  if (divi(a1, b1) && divi(a2, b2)) return 1;
  return 0;
}
void solve(int kase) {
  cin >> a >> b;
  if (divi(a, b))
    printf("YES\n");
  else
    printf("NO\n");
}
const bool DUO = 0;
void TIME() {
  clock_t start, finish;
  double totaltime;
  start = clock();
  if (DUO) {
    int Kase = 0;
    cin >> Kase;
    for (int kase = 1; kase <= Kase; kase++) solve(kase);
  } else
    solve(1);
  finish = clock();
  totaltime = (double)(finish - start) / CLOCKS_PER_SEC;
  printf("\nTime:%lfms\n", totaltime * 1000);
}
int main() {
  if (DUO) {
    int Kase = 0;
    cin >> Kase;
    for (int kase = 1; kase <= Kase; kase++) solve(kase);
  } else
    solve(1);
  return 0;
}
