subsums

#include <algorithm>
#include <iostream>
#include <vector>

#define ll long long

std::vector<ll> subsetSumsPartial(std::vector<ll>::iterator beg,
                                  std::vector<ll>::iterator end) {
  uint16_t n{static_cast<uint16_t>(end - beg)};
  std::vector<ll> sums((1 << n), 0);
  for (uint16_t i{1}; i < (1 << n); i++) {
    ll sum{0};
    uint16_t j{i}, pos{0};
    while (j) {
      if (j & 1) sum += *(beg + pos);
      pos++;
      j >>= 1;
    }
    sums[i] = sum;
  }
  return sums;
}

ll subsetSumsTotal(const std::vector<ll> &sum1, const std::vector<ll> &sum2,
                   int a, int b) {
  ll ans{0};
  for (auto x : sum1) {
    auto lit = std::lower_bound(sum2.begin(), sum2.end(), a - x);
    auto hit = std::upper_bound(sum2.begin(), sum2.end(), b - x);
    ans += (hit - lit);
  }
  return ans;
}

int main() {
  uint16_t n{};
  int a{}, b{};
  std::cin >> n >> a >> b;
  std::vector<ll> v(n);
  for (uint16_t i{0}; i < n; i++) std::cin >> v[i];
  std::vector<ll> sum1{subsetSumsPartial(v.begin(), (v.begin() + n / 2))};
  std::vector<ll> sum2{subsetSumsPartial(v.begin() + n / 2, v.end())};
  std::sort(sum2.begin(), sum2.end());
  std::cout << subsetSumsTotal(sum1, sum2, a, b) << '\n';
  return 0;
}