#include <bits/stdc++.h>
using namespace std;
string str;
long long int x, t, z, y, p, q, a, b, c, d, e, f, n, len, tot, ans, step;
template <class T, class X>
inline T _bigmod(T n, X m) {
  unsigned long long int ret = 1, a = n % 1000000007;
  while (m) {
    if (m & 1) ret = (ret * a) % 1000000007;
    m >>= 1;
    a = (a * a) % 1000000007;
  }
  ret %= 1000000007;
  return (T)ret;
}
template <class T>
inline T _modinv(T n) {
  return _bigmod(n, 1000000007 - 2);
}
int main() {
  cin >> str;
  n = str.size();
  tot = ((_bigmod(2, n) % 1000000007) - 1 + 1000000007) % 1000000007;
  tot = ((tot * (_bigmod(2, n - 1) % 1000000007) + 1000000007) % 1000000007 +
         1000000007) %
        1000000007;
  len = str.size();
  ans = 0;
  for (int i = 0; i < len; i++) {
    if (str[i] == '0')
      ans = ((ans + (_bigmod(2, len - 1 - i) % 1000000007) + 1000000007) %
                 1000000007 +
             1000000007) %
            1000000007;
  }
  step = (ans * _bigmod(2, n - 1)) % 1000000007;
  ans = ((tot - step + 1000000007) % 1000000007 + 1000000007) % 1000000007;
  cout << ans << endl;
  return 0;
}
