Problem: 

Input

The input consists of a single string of uppercase letters A-Z. The length of the string is between 1 and 10 characters, inclusive.

Output

Output "YES" or "NO".

Examples

Input


GENIUS


Output


YES


Input


DOCTOR


Output


NO


Input


IRENE


Output


YES


Input


MARY


Output


NO


Input


SMARTPHONE


Output


NO


Input


REVOLVER


Output


YES


Input


HOLMES


Output


NO


Input


WATSON


Output


YES

Solution (in CPP):

Solution:
#include <bits/stdc++.h>
using namespace std;
const long long INF(0x3f3f3f3f3f3f3f3fll);
const long long inf(0x3f3f3f3f);
template <typename T>
void read(T &res) {
  bool flag = false;
  char ch;
  while (!isdigit(ch = getchar())) (ch == '-') && (flag = true);
  for (res = ch - 48; isdigit(ch = getchar());
       res = (res << 1) + (res << 3) + ch - 48)
    ;
  flag && (res = -res);
}
template <typename T>
void Out(T x) {
  if (x < 0) putchar('-'), x = -x;
  if (x > 9) Out(x / 10);
  putchar(x % 10 + '0');
}
long long gcd(long long a, long long b) { return b ? gcd(b, a % b) : a; }
long long lcm(long long a, long long b) { return a * b / gcd(a, b); }
long long pow_mod(long long x, long long n, long long mod) {
  long long res = 1;
  while (n) {
    if (n & 1) res = res * x % mod;
    x = x * x % mod;
    n >>= 1;
  }
  return res;
}
long long fact_pow(long long n, long long p) {
  long long res = 0;
  while (n) {
    n /= p;
    res += n;
  }
  return res;
}
long long mult(long long a, long long b, long long p) {
  a %= p;
  b %= p;
  long long r = 0, v = a;
  while (b) {
    if (b & 1) {
      r += v;
      if (r > p) r -= p;
    }
    v <<= 1;
    if (v > p) v -= p;
    b >>= 1;
  }
  return r;
}
long long quick_pow(long long a, long long b, long long p) {
  long long r = 1, v = a % p;
  while (b) {
    if (b & 1) r = mult(r, v, p);
    v = mult(v, v, p);
    b >>= 1;
  }
  return r;
}
bool CH(long long a, long long n, long long x, long long t) {
  long long r = quick_pow(a, x, n);
  long long z = r;
  for (long long i = 1; i <= t; i++) {
    r = mult(r, r, n);
    if (r == 1 && z != 1 && z != n - 1) return true;
    z = r;
  }
  return r != 1;
}
bool Miller_Rabin(long long n) {
  if (n < 2) return false;
  if (n == 2) return true;
  if (!(n & 1)) return false;
  long long x = n - 1, t = 0;
  while (!(x & 1)) {
    x >>= 1;
    t++;
  }
  srand(time(NULL));
  long long o = 8;
  for (long long i = 0; i < o; i++) {
    long long a = rand() % (n - 1) + 1;
    if (CH(a, n, x, t)) return false;
  }
  return true;
}
void exgcd(long long a, long long b, long long &x, long long &y) {
  if (!b) {
    x = 1, y = 0;
    return;
  }
  exgcd(b, a % b, x, y);
  long long t = x;
  x = y, y = t - (a / b) * y;
}
long long inv(long long a, long long b) {
  long long x, y;
  return exgcd(a, b, x, y), (x % b + b) % b;
}
long long crt(long long x, long long p, long long mod) {
  return inv(p / mod, mod) * (p / mod) * x;
}
long long fac(long long x, long long a, long long b) {
  if (!x) return 1;
  long long ans = 1;
  for (long long i = 1; i <= b; i++)
    if (i % a) ans *= i, ans %= b;
  ans = pow_mod(ans, x / b, b);
  for (long long i = 1; i <= x % b; i++)
    if (i % a) ans *= i, ans %= b;
  return ans * fac(x / a, a, b) % b;
}
long long C(long long n, long long m, long long a, long long b) {
  long long N = fac(n, a, b), M = fac(m, a, b), Z = fac(n - m, a, b), sum = 0,
            i;
  for (i = n; i; i = i / a) sum += i / a;
  for (i = m; i; i = i / a) sum -= i / a;
  for (i = n - m; i; i = i / a) sum -= i / a;
  return N * pow_mod(a, sum, b) % b * inv(M, b) % b * inv(Z, b) % b;
}
long long exlucas(long long n, long long m, long long p) {
  long long t = p, ans = 0, i;
  for (i = 2; i * i <= p; i++) {
    long long k = 1;
    while (t % i == 0) {
      k *= i, t /= i;
    }
    ans += crt(C(n, m, i, k), p, k), ans %= p;
  }
  if (t > 1) ans += crt(C(n, m, t, t), p, t), ans %= p;
  return ans % p;
}
const long long N = 2e5 + 10;
string table[119] = {
    "H",  "HE", "LI", "BE", "B",  "C",  "N",  "O",  "F",  "NE", "NA", "MG",
    "AL", "SI", "P",  "S",  "CL", "AR", "K",  "CA", "SC", "TI", "V",  "CR",
    "MN", "FE", "CO", "NI", "CU", "ZN", "GA", "GE", "AS", "SE", "BR", "KR",
    "RB", "SR", "Y",  "ZR", "NB", "MO", "TC", "RU", "RH", "PD", "AG", "CD",
    "IN", "SN", "SB", "TE", "I",  "XE", "CS", "BA", "LA", "CE", "PR", "ND",
    "PM", "SM", "EU", "GD", "TB", "DY", "HO", "ER", "TM", "YB", "LU", "HF",
    "TA", "W",  "RE", "OS", "IR", "PT", "AU", "HG", "TL", "PB", "BI", "PO",
    "AT", "RN", "FR", "RA", "AC", "TH", "PA", "U",  "NP", "PU", "AM", "CM",
    "BK", "CF", "ES", "FM", "MD", "NO", "LR", "RF", "DB", "SG", "BH", "HS",
    "MT", "DS", "RG", "CN", "NH", "FL", "MC", "LV", "TS", "OG", ""};
long long len;
map<string, long long> vis;
long long ans;
string s;
long long book[N];
void dfs(long long now, long long flag) {
  if (!flag) return;
  if (now > len) {
    ans = max(ans, flag);
    return;
  }
  string a = "";
  a += s[now];
  if (vis[a]) dfs(now + 1, 1);
  if (now + 1 <= len) {
    a += s[now + 1];
    if (vis[a]) dfs(now + 2, 1);
  }
}
signed main() {
  std::ios::sync_with_stdio(false);
  cin >> s;
  len = s.size() - 1;
  for (long long i = 0; i <= 118; i++) vis[table[i]]++;
  dfs(0, 1);
  if (ans)
    cout << "YES\n";
  else
    cout << "NO\n";
  return 0;
}