Problem p03776 (C++)

Buggy submission (status: Time Limit Exceeded):
#include <algorithm>
#include <bits/stdc++.h>
#include <bitset>
#include <cassert>
#include <cctype>
#include <cmath>
#include <cstdio>
#include <fstream>
#include <functional>
#include <iostream>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <stdio.h>
#include <string.h>
#include <string>
#include <utility>
#include <vector>

#include <cstdint>
#include <cstring>
#include <iomanip>
using namespace std;
using ll = long long;
#define ALL(a) (a).begin(), (a).end()

#define FOR(i, a, b) for (long long int i = (a); i <= (b); i++)
#define RFOR(i, a, b) for (long long int i = (a); i >= (b); i--)

const int MOD = 1000000007;

#define LLONG_MAXs 9223372036854775800 / 2
// #define bit(n, k) ((n >> k) & 1) /*nのk bit目*/
#define ALL(a) (a).begin(), (a).end()

#include <cmath>
#include <iostream>
using namespace std;

bool isPrimeNum(ll x) { // 素数である場合 true を返す
  if (x <= 1) { // 1以下である場合は素数でないことがすぐにわかる
    return false;
  }
  // sqrt( double型 ) は引数の平方根を double型で返すので、int型でキャスト
  int n = (int)sqrt((double)x);
  for (int i = 2; i <= n; i++) {
    if (x % i == 0) { // 割り切る整数がある場合、即判定終了
      return false;
    }
  }
  return true; // 割り切る整数がない場合、素数である
}

ll myPow(ll x, ll n, ll m) {
  if (n == 0)
    return 1;
  if (n % 2 == 0)
    return myPow(x * x % m, n / 2, m);
  else
    return x * myPow(x, n - 1, m) % m;
}

constexpr ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }
constexpr ll lcm(ll a, ll b) { return a * b / gcd(a, b); }
constexpr ll abs(ll a, ll b) {
  if (a >= b)
    return a - b;
  if (a < b)
    return b - a;
}
constexpr double dabs(double a, double b) {
  if (a >= b)
    return a - b;
  if (a < b)
    return b - a;
}
constexpr ll min(ll a, ll b) {
  if (a >= b)
    return b;
  if (a < b)
    return a;
}

constexpr ll max(ll a, ll b) {
  if (a >= b)
    return a;
  if (a < b)
    return b;
}

int dx[4] = {1, 0, -1, 0};
int dy[4] = {0, 1, 0, -1};

int dx8[8] = {1, 0, -1, 0, 1, -1, 1, -1};
int dy8[8] = {0, 1, 0, -1, 1, 1, -1, -1};

class UnionFind {
public:
  // 親の番号を格納する。親だった場合は-(その集合のサイズ)
  vector<int> Parent;

  // 作るときはParentの値を全て-1にする
  // こうすると全てバラバラになる
  UnionFind(int N) { Parent = vector<int>(N, -1); }

  // Aがどのグループに属しているか調べる
  int root(int A) {
    if (Parent[A] < 0)
      return A;
    return Parent[A] = root(Parent[A]);
  }

  // 自分のいるグループの頂点数を調べる
  int size(int A) {
    return -Parent[root(A)]; // 親をとってきたい]
  }
  bool issame(int x, int y) { return root(x) == root(y); }
  // AとBをくっ付ける
  bool connect(int A, int B) {
    // AとBを直接つなぐのではなく、root(A)にroot(B)をくっつける
    A = root(A);
    B = root(B);
    if (A == B) {
      // すでにくっついてるからくっ付けない
      return false;
    }

    // 大きい方(A)に小さいほう(B)をくっ付けたい
    // 大小が逆だったらひっくり返しちゃう。
    if (size(A) < size(B))
      swap(A, B);

    // Aのサイズを更新する
    Parent[A] += Parent[B];
    // Bの親をAに変更する
    Parent[B] = A;

    return true;
  }
};

long long fac[510000], finv[510000], inv[510000];

// テーブルを作る前処理
void COMinit() {
  fac[0] = fac[1] = 1;
  finv[0] = finv[1] = 1;
  inv[1] = 1;
  for (int i = 2; i < 510000; i++) {
    fac[i] = fac[i - 1] * i % MOD;
    inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD;
    finv[i] = finv[i - 1] * inv[i] % MOD;
  }
}

// 二項係数計算
long long COM(int n, int k) {
  if (n < k)
    return 0;
  if (n < 0 || k < 0)
    return 0;
  return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;
}

long long modinv(long long a, long long m) {
  long long b = m, u = 1, v = 0;
  while (b) {
    long long t = a / b;
    a -= t * b;
    swap(a, b);
    u -= t * v;
    swap(u, v);
  }
  u %= m;
  if (u < 0)
    u += m;
  return u;
}

void yn(bool flag) {
  if (flag) {
    cout << "Yes" << endl;
  } else {
    cout << "No" << endl;
  }
  return;
}
void YN(bool flag) {
  if (flag) {
    cout << "YES" << endl;
  } else {
    cout << "NO" << endl;
  }
  return;
}

std::vector<ll> enum_div(ll n) // nの約数を列挙
{
  std::vector<ll> ret;
  for (ll i = 1; i * i <= n; ++i) {
    if (n % i == 0) {
      ret.push_back(i);
      if (i != 1 && i * i != n) {
        ret.push_back(n / i);
      }
    }
  }
  ret.push_back(n);
  return ret;
}

// modint: mod 計算を int を扱うように扱える構造体
template <int MOD> struct Fp {
  long long val;
  constexpr Fp(long long v = 0) noexcept : val(v % MOD) {
    if (val < 0)
      val += MOD;
  }
  constexpr int getmod() { return MOD; }
  constexpr Fp operator-() const noexcept { return val ? MOD - val : 0; }
  constexpr Fp operator+(const Fp &r) const noexcept { return Fp(*this) += r; }
  constexpr Fp operator-(const Fp &r) const noexcept { return Fp(*this) -= r; }
  constexpr Fp operator*(const Fp &r) const noexcept { return Fp(*this) *= r; }
  constexpr Fp operator/(const Fp &r) const noexcept { return Fp(*this) /= r; }
  constexpr Fp &operator+=(const Fp &r) noexcept {
    val += r.val;
    if (val >= MOD)
      val -= MOD;
    return *this;
  }
  constexpr Fp &operator-=(const Fp &r) noexcept {
    val -= r.val;
    if (val < 0)
      val += MOD;
    return *this;
  }
  constexpr Fp &operator*=(const Fp &r) noexcept {
    val = val * r.val % MOD;
    return *this;
  }
  constexpr Fp &operator/=(const Fp &r) noexcept {
    long long a = r.val, b = MOD, u = 1, v = 0;
    while (b) {
      long long t = a / b;
      a -= t * b;
      swap(a, b);
      u -= t * v;
      swap(u, v);
    }
    val = val * u % MOD;
    if (val < 0)
      val += MOD;
    return *this;
  }
  constexpr bool operator==(const Fp &r) const noexcept {
    return this->val == r.val;
  }
  constexpr bool operator!=(const Fp &r) const noexcept {
    return this->val != r.val;
  }
  friend constexpr ostream &operator<<(ostream &os, const Fp<MOD> &x) noexcept {
    return os << x.val;
  }
  friend constexpr Fp<MOD> modpow(const Fp<MOD> &a, long long n) noexcept {
    if (n == 0)
      return 1;
    auto t = modpow(a, n / 2);
    t = t * t;
    if (n & 1)
      t = t * a;
    return t;
  }
};

using mint = Fp<MOD>;

// グラフセット
struct Edge {
  ll to;     // 辺の行き先
  ll weight; // 辺の重み
  Edge(int t, int w) : to(t), weight(w) {}
};

typedef vector<vector<long long>> matrix;
matrix mul_mod(matrix A, matrix B) {
  int H = A.size();
  int W = B[0].size();
  int K = A[0].size();

  matrix C(H, vector<ll>(W, 0));
  for (int i = 0; i < H; i++) {
    for (int j = 0; j < W; j++) {
      for (int k = 0; k < K; k++) {
        C[i][j] += A[i][k] * B[k][j];
        C[i][j] %= MOD;
      }
    }
  }
  return C;
}

// 区間加算にも対応した BIT
template <class Abel> struct BIT {
  vector<Abel> dat[2];
  Abel UNITY_SUM = 0; // to be set

  /* [1, n] */
  BIT(int n) { init(n); }
  void init(int n) {
    for (int iter = 0; iter < 2; ++iter)
      dat[iter].assign(n + 1, UNITY_SUM);
  }

  /* a, b are 1-indexed, [a, b) */
  inline void sub_add(int p, int a, Abel x) {
    for (int i = a; i < (int)dat[p].size(); i += i & -i)
      dat[p][i] = dat[p][i] + x;
  }
  inline void add(int a, int b, Abel x) {
    sub_add(0, a, x * -(a - 1));
    sub_add(1, a, x);
    sub_add(0, b, x * (b - 1));
    sub_add(1, b, x * (-1));
  }

  /* a is 1-indexed, [a, b) */
  inline Abel sub_sum(int p, int a) {
    Abel res = UNITY_SUM;
    for (int i = a; i > 0; i -= i & -i)
      res = res + dat[p][i];
    return res;
  }
  inline Abel sum(int a, int b) {
    return sub_sum(0, b - 1) + sub_sum(1, b - 1) * (b - 1) - sub_sum(0, a - 1) -
           sub_sum(1, a - 1) * (a - 1);
  }

  /* debug */
  void print() {
    for (int i = 1; i < (int)dat[0].size(); ++i)
      cout << sum(i, i + 1) << ",";
    cout << endl;
  }
};
// cout << std::setprecision(30) << ans << endl;

using Graph = vector<vector<ll>>;

void print(const std::vector<int> &v) {
  std::for_each(v.begin(), v.end(), [](int x) { std::cout << x << " "; });
  std::cout << std::endl;
}
const double PI = 3.14159265358979323846;
ll times_cap(ll a, ll b) {
  if (log10(a) + log10(b) >= 19.0)
    return -1;
  else
    return a * b;
}
// cout<<std::setprecision(30)
#include <functional>
#include <iostream>
#include <vector>
using namespace std;

// Segment Tree
template <class Monoid, class Action> struct SegTree {
  using FuncMonoid = function<Monoid(Monoid, Monoid)>;
  using FuncAction = function<void(Monoid &, Action)>;
  using FuncLazy = function<void(Action &, Action)>;
  FuncMonoid FM;
  FuncAction FA;
  FuncLazy FL;
  Monoid UNITY_MONOID;
  Action UNITY_LAZY;
  int SIZE, HEIGHT;
  vector<Monoid> dat;
  vector<Action> lazy;

  SegTree() {}
  SegTree(int n, const FuncMonoid fm, const FuncAction fa, const FuncLazy fl,
          const Monoid &unity_monoid, const Action &unity_lazy)
      : FM(fm), FA(fa), FL(fl), UNITY_MONOID(unity_monoid),
        UNITY_LAZY(unity_lazy) {
    SIZE = 1;
    HEIGHT = 0;
    while (SIZE < n)
      SIZE <<= 1, ++HEIGHT;
    dat.assign(SIZE * 2, UNITY_MONOID);
    lazy.assign(SIZE * 2, UNITY_LAZY);
  }
  void init(int n, const FuncMonoid fm, const FuncAction fa, const FuncLazy fl,
            const Monoid &unity_monoid, const Action &unity_lazy) {
    FM = fm;
    FA = fa;
    FL = fl;
    UNITY_MONOID = unity_monoid;
    UNITY_LAZY = unity_lazy;
    SIZE = 1;
    HEIGHT = 0;
    while (SIZE < n)
      SIZE <<= 1, ++HEIGHT;
    dat.assign(SIZE * 2, UNITY_MONOID);
    lazy.assign(SIZE * 2, UNITY_LAZY);
  }

  /* set, a is 0-indexed */
  void set(int a, const Monoid &v) { dat[a + SIZE] = v; }
  void build() {
    for (int k = SIZE - 1; k > 0; --k)
      dat[k] = FM(dat[k * 2], dat[k * 2 + 1]);
  }

  /* update [a, b) */
  inline void evaluate(int k) {
    if (lazy[k] == UNITY_LAZY)
      return;
    if (k < SIZE)
      FL(lazy[k * 2], lazy[k]), FL(lazy[k * 2 + 1], lazy[k]);
    FA(dat[k], lazy[k]);
    lazy[k] = UNITY_LAZY;
  }
  inline void update(int a, int b, const Action &v, int k, int l, int r) {
    evaluate(k);
    if (a <= l && r <= b)
      FL(lazy[k], v), evaluate(k);
    else if (a < r && l < b) {
      update(a, b, v, k * 2, l, (l + r) >> 1),
          update(a, b, v, k * 2 + 1, (l + r) >> 1, r);
      dat[k] = FM(dat[k * 2], dat[k * 2 + 1]);
    }
  }
  inline void update(int a, int b, const Action &v) {
    update(a, b, v, 1, 0, SIZE);
  }

  /* get [a, b) */
  inline Monoid get(int a, int b, int k, int l, int r) {
    evaluate(k);
    if (a <= l && r <= b)
      return dat[k];
    else if (a < r && l < b)
      return FM(get(a, b, k * 2, l, (l + r) >> 1),
                get(a, b, k * 2 + 1, (l + r) >> 1, r));
    else
      return UNITY_MONOID;
  }
  inline Monoid get(int a, int b) { return get(a, b, 1, 0, SIZE); }
  inline Monoid operator[](int a) { return get(a, a + 1); }

  /* debug */
  void print() {
    for (int i = 0; i < SIZE; ++i) {
      cout << (*this)[i];
      if (i != SIZE)
        cout << ",";
    }
    cout << endl;
  }
};

vector<int> IntegerToVector(int bit, int N) {
  vector<int> S;
  for (int i = 0; i < N; ++i) {
    if (bit & (1 << i)) {
      S.push_back(i);
    }
  }
  return S;
}
std::vector<std::vector<long long>> comb(int n, int r) {
  std::vector<std::vector<long long>> v(n + 1,
                                        std::vector<long long>(n + 1, 0));
  for (int i = 0; i < v.size(); i++) {
    v[i][0] = 1;
    v[i][i] = 1;
  }
  for (int j = 1; j < v.size(); j++) {
    for (int k = 1; k < j; k++) {
      v[j][k] = (v[j - 1][k - 1] + v[j - 1][k]);
    }
  }
  return v;
}
int main() {
  // 前処理
  COMinit();

  ll N, A, B;
  cin >> N >> A >> B;
  ll v[N];
  FOR(i, 0, N - 1) { cin >> v[i]; }

  sort(v, v + N);
  ll sum = 0;
  ll min = v[N - A];
  FOR(i, N - A, N - 1) { sum = sum + v[i]; }

  double avg = (double)sum / (double)A;
  cout << setprecision(20) << (double)avg << endl;

  ll ans = 0;
  ll count = 0;
  ll koe = 0;
  FOR(i, 0, N - 1) {
    if (min == v[i])
      count++;
    if (min < v[i])
      koe++;
  }

  auto com = comb(51, 51);

  ll yoyuu = A - koe;
  if (koe == 0) {

    FOR(i, A, B) { ans += com[count][i]; }
  } else {
    while (1) {
    }
  }

  cout << ans << endl;

  return 0;
}

Fixed submission:
#include <algorithm>
#include <bits/stdc++.h>
#include <bitset>
#include <cassert>
#include <cctype>
#include <cmath>
#include <cstdio>
#include <fstream>
#include <functional>
#include <iostream>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <stdio.h>
#include <string.h>
#include <string>
#include <utility>
#include <vector>

#include <cstdint>
#include <cstring>
#include <iomanip>
using namespace std;
using ll = long long;
#define ALL(a) (a).begin(), (a).end()

#define FOR(i, a, b) for (long long int i = (a); i <= (b); i++)
#define RFOR(i, a, b) for (long long int i = (a); i >= (b); i--)

const int MOD = 1000000007;

#define LLONG_MAXs 9223372036854775800 / 2
// #define bit(n, k) ((n >> k) & 1) /*nのk bit目*/
#define ALL(a) (a).begin(), (a).end()

#include <cmath>
#include <iostream>
using namespace std;

bool isPrimeNum(ll x) { // 素数である場合 true を返す
  if (x <= 1) { // 1以下である場合は素数でないことがすぐにわかる
    return false;
  }
  // sqrt( double型 ) は引数の平方根を double型で返すので、int型でキャスト
  int n = (int)sqrt((double)x);
  for (int i = 2; i <= n; i++) {
    if (x % i == 0) { // 割り切る整数がある場合、即判定終了
      return false;
    }
  }
  return true; // 割り切る整数がない場合、素数である
}

ll myPow(ll x, ll n, ll m) {
  if (n == 0)
    return 1;
  if (n % 2 == 0)
    return myPow(x * x % m, n / 2, m);
  else
    return x * myPow(x, n - 1, m) % m;
}

constexpr ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }
constexpr ll lcm(ll a, ll b) { return a * b / gcd(a, b); }
constexpr ll abs(ll a, ll b) {
  if (a >= b)
    return a - b;
  if (a < b)
    return b - a;
}
constexpr double dabs(double a, double b) {
  if (a >= b)
    return a - b;
  if (a < b)
    return b - a;
}
constexpr ll min(ll a, ll b) {
  if (a >= b)
    return b;
  if (a < b)
    return a;
}

constexpr ll max(ll a, ll b) {
  if (a >= b)
    return a;
  if (a < b)
    return b;
}

int dx[4] = {1, 0, -1, 0};
int dy[4] = {0, 1, 0, -1};

int dx8[8] = {1, 0, -1, 0, 1, -1, 1, -1};
int dy8[8] = {0, 1, 0, -1, 1, 1, -1, -1};

class UnionFind {
public:
  // 親の番号を格納する。親だった場合は-(その集合のサイズ)
  vector<int> Parent;

  // 作るときはParentの値を全て-1にする
  // こうすると全てバラバラになる
  UnionFind(int N) { Parent = vector<int>(N, -1); }

  // Aがどのグループに属しているか調べる
  int root(int A) {
    if (Parent[A] < 0)
      return A;
    return Parent[A] = root(Parent[A]);
  }

  // 自分のいるグループの頂点数を調べる
  int size(int A) {
    return -Parent[root(A)]; // 親をとってきたい]
  }
  bool issame(int x, int y) { return root(x) == root(y); }
  // AとBをくっ付ける
  bool connect(int A, int B) {
    // AとBを直接つなぐのではなく、root(A)にroot(B)をくっつける
    A = root(A);
    B = root(B);
    if (A == B) {
      // すでにくっついてるからくっ付けない
      return false;
    }

    // 大きい方(A)に小さいほう(B)をくっ付けたい
    // 大小が逆だったらひっくり返しちゃう。
    if (size(A) < size(B))
      swap(A, B);

    // Aのサイズを更新する
    Parent[A] += Parent[B];
    // Bの親をAに変更する
    Parent[B] = A;

    return true;
  }
};

long long fac[510000], finv[510000], inv[510000];

// テーブルを作る前処理
void COMinit() {
  fac[0] = fac[1] = 1;
  finv[0] = finv[1] = 1;
  inv[1] = 1;
  for (int i = 2; i < 510000; i++) {
    fac[i] = fac[i - 1] * i % MOD;
    inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD;
    finv[i] = finv[i - 1] * inv[i] % MOD;
  }
}

// 二項係数計算
long long COM(int n, int k) {
  if (n < k)
    return 0;
  if (n < 0 || k < 0)
    return 0;
  return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;
}

long long modinv(long long a, long long m) {
  long long b = m, u = 1, v = 0;
  while (b) {
    long long t = a / b;
    a -= t * b;
    swap(a, b);
    u -= t * v;
    swap(u, v);
  }
  u %= m;
  if (u < 0)
    u += m;
  return u;
}

void yn(bool flag) {
  if (flag) {
    cout << "Yes" << endl;
  } else {
    cout << "No" << endl;
  }
  return;
}
void YN(bool flag) {
  if (flag) {
    cout << "YES" << endl;
  } else {
    cout << "NO" << endl;
  }
  return;
}

std::vector<ll> enum_div(ll n) // nの約数を列挙
{
  std::vector<ll> ret;
  for (ll i = 1; i * i <= n; ++i) {
    if (n % i == 0) {
      ret.push_back(i);
      if (i != 1 && i * i != n) {
        ret.push_back(n / i);
      }
    }
  }
  ret.push_back(n);
  return ret;
}

// modint: mod 計算を int を扱うように扱える構造体
template <int MOD> struct Fp {
  long long val;
  constexpr Fp(long long v = 0) noexcept : val(v % MOD) {
    if (val < 0)
      val += MOD;
  }
  constexpr int getmod() { return MOD; }
  constexpr Fp operator-() const noexcept { return val ? MOD - val : 0; }
  constexpr Fp operator+(const Fp &r) const noexcept { return Fp(*this) += r; }
  constexpr Fp operator-(const Fp &r) const noexcept { return Fp(*this) -= r; }
  constexpr Fp operator*(const Fp &r) const noexcept { return Fp(*this) *= r; }
  constexpr Fp operator/(const Fp &r) const noexcept { return Fp(*this) /= r; }
  constexpr Fp &operator+=(const Fp &r) noexcept {
    val += r.val;
    if (val >= MOD)
      val -= MOD;
    return *this;
  }
  constexpr Fp &operator-=(const Fp &r) noexcept {
    val -= r.val;
    if (val < 0)
      val += MOD;
    return *this;
  }
  constexpr Fp &operator*=(const Fp &r) noexcept {
    val = val * r.val % MOD;
    return *this;
  }
  constexpr Fp &operator/=(const Fp &r) noexcept {
    long long a = r.val, b = MOD, u = 1, v = 0;
    while (b) {
      long long t = a / b;
      a -= t * b;
      swap(a, b);
      u -= t * v;
      swap(u, v);
    }
    val = val * u % MOD;
    if (val < 0)
      val += MOD;
    return *this;
  }
  constexpr bool operator==(const Fp &r) const noexcept {
    return this->val == r.val;
  }
  constexpr bool operator!=(const Fp &r) const noexcept {
    return this->val != r.val;
  }
  friend constexpr ostream &operator<<(ostream &os, const Fp<MOD> &x) noexcept {
    return os << x.val;
  }
  friend constexpr Fp<MOD> modpow(const Fp<MOD> &a, long long n) noexcept {
    if (n == 0)
      return 1;
    auto t = modpow(a, n / 2);
    t = t * t;
    if (n & 1)
      t = t * a;
    return t;
  }
};

using mint = Fp<MOD>;

// グラフセット
struct Edge {
  ll to;     // 辺の行き先
  ll weight; // 辺の重み
  Edge(int t, int w) : to(t), weight(w) {}
};

typedef vector<vector<long long>> matrix;
matrix mul_mod(matrix A, matrix B) {
  int H = A.size();
  int W = B[0].size();
  int K = A[0].size();

  matrix C(H, vector<ll>(W, 0));
  for (int i = 0; i < H; i++) {
    for (int j = 0; j < W; j++) {
      for (int k = 0; k < K; k++) {
        C[i][j] += A[i][k] * B[k][j];
        C[i][j] %= MOD;
      }
    }
  }
  return C;
}

// 区間加算にも対応した BIT
template <class Abel> struct BIT {
  vector<Abel> dat[2];
  Abel UNITY_SUM = 0; // to be set

  /* [1, n] */
  BIT(int n) { init(n); }
  void init(int n) {
    for (int iter = 0; iter < 2; ++iter)
      dat[iter].assign(n + 1, UNITY_SUM);
  }

  /* a, b are 1-indexed, [a, b) */
  inline void sub_add(int p, int a, Abel x) {
    for (int i = a; i < (int)dat[p].size(); i += i & -i)
      dat[p][i] = dat[p][i] + x;
  }
  inline void add(int a, int b, Abel x) {
    sub_add(0, a, x * -(a - 1));
    sub_add(1, a, x);
    sub_add(0, b, x * (b - 1));
    sub_add(1, b, x * (-1));
  }

  /* a is 1-indexed, [a, b) */
  inline Abel sub_sum(int p, int a) {
    Abel res = UNITY_SUM;
    for (int i = a; i > 0; i -= i & -i)
      res = res + dat[p][i];
    return res;
  }
  inline Abel sum(int a, int b) {
    return sub_sum(0, b - 1) + sub_sum(1, b - 1) * (b - 1) - sub_sum(0, a - 1) -
           sub_sum(1, a - 1) * (a - 1);
  }

  /* debug */
  void print() {
    for (int i = 1; i < (int)dat[0].size(); ++i)
      cout << sum(i, i + 1) << ",";
    cout << endl;
  }
};
// cout << std::setprecision(30) << ans << endl;

using Graph = vector<vector<ll>>;

void print(const std::vector<int> &v) {
  std::for_each(v.begin(), v.end(), [](int x) { std::cout << x << " "; });
  std::cout << std::endl;
}
const double PI = 3.14159265358979323846;
ll times_cap(ll a, ll b) {
  if (log10(a) + log10(b) >= 19.0)
    return -1;
  else
    return a * b;
}
// cout<<std::setprecision(30)
#include <functional>
#include <iostream>
#include <vector>
using namespace std;

// Segment Tree
template <class Monoid, class Action> struct SegTree {
  using FuncMonoid = function<Monoid(Monoid, Monoid)>;
  using FuncAction = function<void(Monoid &, Action)>;
  using FuncLazy = function<void(Action &, Action)>;
  FuncMonoid FM;
  FuncAction FA;
  FuncLazy FL;
  Monoid UNITY_MONOID;
  Action UNITY_LAZY;
  int SIZE, HEIGHT;
  vector<Monoid> dat;
  vector<Action> lazy;

  SegTree() {}
  SegTree(int n, const FuncMonoid fm, const FuncAction fa, const FuncLazy fl,
          const Monoid &unity_monoid, const Action &unity_lazy)
      : FM(fm), FA(fa), FL(fl), UNITY_MONOID(unity_monoid),
        UNITY_LAZY(unity_lazy) {
    SIZE = 1;
    HEIGHT = 0;
    while (SIZE < n)
      SIZE <<= 1, ++HEIGHT;
    dat.assign(SIZE * 2, UNITY_MONOID);
    lazy.assign(SIZE * 2, UNITY_LAZY);
  }
  void init(int n, const FuncMonoid fm, const FuncAction fa, const FuncLazy fl,
            const Monoid &unity_monoid, const Action &unity_lazy) {
    FM = fm;
    FA = fa;
    FL = fl;
    UNITY_MONOID = unity_monoid;
    UNITY_LAZY = unity_lazy;
    SIZE = 1;
    HEIGHT = 0;
    while (SIZE < n)
      SIZE <<= 1, ++HEIGHT;
    dat.assign(SIZE * 2, UNITY_MONOID);
    lazy.assign(SIZE * 2, UNITY_LAZY);
  }

  /* set, a is 0-indexed */
  void set(int a, const Monoid &v) { dat[a + SIZE] = v; }
  void build() {
    for (int k = SIZE - 1; k > 0; --k)
      dat[k] = FM(dat[k * 2], dat[k * 2 + 1]);
  }

  /* update [a, b) */
  inline void evaluate(int k) {
    if (lazy[k] == UNITY_LAZY)
      return;
    if (k < SIZE)
      FL(lazy[k * 2], lazy[k]), FL(lazy[k * 2 + 1], lazy[k]);
    FA(dat[k], lazy[k]);
    lazy[k] = UNITY_LAZY;
  }
  inline void update(int a, int b, const Action &v, int k, int l, int r) {
    evaluate(k);
    if (a <= l && r <= b)
      FL(lazy[k], v), evaluate(k);
    else if (a < r && l < b) {
      update(a, b, v, k * 2, l, (l + r) >> 1),
          update(a, b, v, k * 2 + 1, (l + r) >> 1, r);
      dat[k] = FM(dat[k * 2], dat[k * 2 + 1]);
    }
  }
  inline void update(int a, int b, const Action &v) {
    update(a, b, v, 1, 0, SIZE);
  }

  /* get [a, b) */
  inline Monoid get(int a, int b, int k, int l, int r) {
    evaluate(k);
    if (a <= l && r <= b)
      return dat[k];
    else if (a < r && l < b)
      return FM(get(a, b, k * 2, l, (l + r) >> 1),
                get(a, b, k * 2 + 1, (l + r) >> 1, r));
    else
      return UNITY_MONOID;
  }
  inline Monoid get(int a, int b) { return get(a, b, 1, 0, SIZE); }
  inline Monoid operator[](int a) { return get(a, a + 1); }

  /* debug */
  void print() {
    for (int i = 0; i < SIZE; ++i) {
      cout << (*this)[i];
      if (i != SIZE)
        cout << ",";
    }
    cout << endl;
  }
};

vector<int> IntegerToVector(int bit, int N) {
  vector<int> S;
  for (int i = 0; i < N; ++i) {
    if (bit & (1 << i)) {
      S.push_back(i);
    }
  }
  return S;
}
std::vector<std::vector<long long>> comb(int n, int r) {
  std::vector<std::vector<long long>> v(n + 1,
                                        std::vector<long long>(n + 1, 0));
  for (int i = 0; i < v.size(); i++) {
    v[i][0] = 1;
    v[i][i] = 1;
  }
  for (int j = 1; j < v.size(); j++) {
    for (int k = 1; k < j; k++) {
      v[j][k] = (v[j - 1][k - 1] + v[j - 1][k]);
    }
  }
  return v;
}
int main() {
  // 前処理
  COMinit();

  ll N, A, B;
  cin >> N >> A >> B;
  ll v[N];
  FOR(i, 0, N - 1) { cin >> v[i]; }

  sort(v, v + N);
  ll sum = 0;
  ll min = v[N - A];
  FOR(i, N - A, N - 1) { sum = sum + v[i]; }

  double avg = (double)sum / (double)A;
  cout << setprecision(20) << (double)avg << endl;

  ll ans = 0;
  ll count = 0;
  ll koe = 0;
  FOR(i, 0, N - 1) {
    if (min == v[i])
      count++;
    if (min < v[i])
      koe++;
  }

  auto com = comb(51, 51);

  ll yoyuu = A - koe;
  if (koe == 0) {

    FOR(i, A, B) { ans += com[count][i]; }
  } else {
    ans = com[count][yoyuu];
  }

  cout << ans << endl;

  return 0;
}