#include <bits/stdc++.h>
using namespace std;
using vi = vector<int>;
using vll = vector<long long>;
using vpii = vector<pair<int, int>>;
using vpll = vector<pair<long long, long long>>;
using ti3 = tuple<int, int, int>;
using vti3 = vector<ti3>;
template <class T, int s>
using va = vector<array<T, s>>;
template <class T, class T2>
using umap = unordered_map<T, T2>;
template <class T>
using uset = unordered_set<T>;
template <class T, class S>
void cmin(T &a, const S &b) {
  if (a > b) a = b;
}
template <class T, class S>
void cmax(T &a, const S &b) {
  if (a < b) a = b;
}
template <class T>
using heap = priority_queue<T, vector<T>, greater<T>>;
template <class T>
using pque = priority_queue<T, vector<T>, function<T(T, T)>>;
template <class T>
inline void hash_combine(size_t &seed, const T &v) {
  hash<T> hasher;
  seed ^= hasher(v) + 0x9e3779b97f4a7c15 + (seed << 6) + (seed >> 2);
}
namespace std {
template <typename S, typename T>
struct hash<pair<S, T>> {
  inline size_t operator()(const pair<S, T> &v) const {
    size_t seed = 0;
    hash_combine(seed, v.first);
    hash_combine(seed, v.second);
    return seed;
  }
};
template <class Tuple, size_t Index = std::tuple_size<Tuple>::value - 1>
struct HashValueImpl {
  static void apply(size_t &seed, Tuple const &tuple) {
    HashValueImpl<Tuple, Index - 1>::apply(seed, tuple);
    hash_combine(seed, std::get<Index>(tuple));
  }
};
template <class Tuple>
struct HashValueImpl<Tuple, 0> {
  static void apply(size_t &seed, Tuple const &tuple) {
    hash_combine(seed, std::get<0>(tuple));
  }
};
template <typename... TT>
struct hash<std::tuple<TT...>> {
  size_t operator()(std::tuple<TT...> const &tt) const {
    size_t seed = 0;
    HashValueImpl<std::tuple<TT...>>::apply(seed, tt);
    return seed;
  }
};
}  // namespace std
template <class T>
int id(vector<T> &a, T b) {
  return lower_bound(a.begin(), a.end(), b) - a.begin();
}
long long pow(long long base, long long i, long long mod) {
  long long a = 1;
  while (i) {
    if (i & 1) {
      a *= base;
      a %= mod;
    }
    base *= base;
    base %= mod;
    i /= 2;
  }
  return a;
}
long long gcd(long long a, long long b) {
  while (b) {
    long long c = a % b;
    a = b;
    b = c;
  }
  return a;
}
long long lcm(long long a, long long b) { return a / gcd(a, b) * b; }
int popcnt(unsigned long long a) { return __builtin_popcountll(a); }
int BitScanF(unsigned long long a) { return __builtin_ctzll(a); }
int BitScanR(unsigned long long a) { return 63 - __builtin_clzll(a); }
template <class T>
class matrix {
 public:
  vector<valarray<T>> obj;
  pair<int, int> s;

 public:
  matrix(pair<int, int> size, T e = 0) : matrix(size.first, size.second, e) {}
  matrix(int n, int m = -1, T e = 0)
      : obj(n, valarray<T>(e, m == -1 ? n : m)), s(n, m == -1 ? n : m) {}
  static matrix e(int n) {
    matrix a = (n);
    for (int i = 0; i < n; i++) a[i][i] = 1;
    return a;
  }
  matrix &operator+=(const matrix &p) {
    if (s != p.s) throw runtime_error("matrix error");
    for (int i = 0; i < s.first; i++)
      for (int j = 0; j < s.second; j++) obj[i][j] += p.obj[i][j];
    return *this;
  }
  matrix operator+(const matrix &p) {
    matrix res(*this);
    return res += p;
  }
  matrix &operator-=(const matrix &p) {
    if (s != p.s) throw runtime_error("matrix error");
    for (int i = 0; i < s.first; i++)
      for (int j = 0; j < s.second; j++) obj[i][j] -= p.obj[i][j];
    return *this;
  }
  matrix operator-(const matrix &p) {
    matrix res(*this);
    return res -= p;
  }
  matrix &operator*=(T p) {
    for (auto &a : obj)
      for (auto &b : a) b *= p;
    return *this;
  }
  matrix operator*(T p) {
    matrix res(*this);
    return res *= p;
  }
  matrix operator*(const matrix &p) {
    if (s.second != p.s.first) throw runtime_error("matrix error");
    matrix ret(s.first, p.s.second);
    for (int i = 0; i < s.first; i++)
      for (int j = 0; j < s.second; j++) ret[i] += obj[i][j] * p.obj[j];
    return ret;
  }
  matrix &operator*=(const matrix &p) { return *this = *this * p; }
  bool operator==(const matrix &p) {
    if (s != p.s) return 0;
    for (int i = 0; i < s.first; i++)
      for (int j = 0; j < s.second; j++)
        if (obj[i][j] != p.obj[i][j]) return 0;
    return 1;
  }
  pair<int, int> size() const { return s; }
  matrix &mod(T m) {
    for (auto &a : obj)
      for (auto &b : a) b %= m;
    return *this;
  }
  valarray<T> &operator[](int t) { return obj[t]; }
  void gauss() {
    if (size().first + 1 != size().second) return;
    for (int i = 0; i < size().first; i++) {
      int p = i;
      for (int j = i; j < size().first; j++)
        if (abs(obj[j][i]) > abs(obj[p][i])) p = j;
      swap(obj[i], obj[p]);
      if (abs(obj[i][i]) < 1e-8) return;
      for (int j = i + 1; j < size().second; j++) obj[i][j] /= obj[i][i];
      for (int j = 0; j < size().first; j++) {
        if (i != j) {
          for (int k = i + 1; k < size().second; k++)
            obj[j][k] -= obj[j][i] * obj[i][k];
        }
      }
    }
  }
};
template <class T>
inline matrix<T> pow(matrix<T> &base, unsigned long long exp) {
  auto base_(base);
  if (base_.size().first != base_.size().second)
    throw runtime_error("matrix error");
  matrix<T> res = matrix<T>::e(base_.size().first);
  for (;;) {
    if (exp & 1) res *= base_;
    if (res.obj[0].size() > 100) {
      int a = 0;
    }
    if (!(exp /= 2)) break;
    base_ *= base_;
  }
  return res;
}
template <class T>
inline matrix<T> modpow(matrix<T> &base, unsigned long long exp, long long m) {
  auto base_(base);
  if (base.size().first != base_.size().second)
    throw runtime_error("matrix error");
  matrix<T> res = matrix<T>::e(base_.size().first);
  for (;;) {
    if (exp & 1) (res *= base_).mod(m);
    if (res.obj[0].size() > 100) {
      int a = 0;
    }
    if (!(exp /= 2)) break;
    (base_ *= base_).mod(m);
  }
  return res;
}
class unionfind {
  vector<int> par, rank, size_;

 public:
  unionfind(int n) : par(n), rank(n), size_(n, 1) {
    iota(par.begin(), par.end(), 0);
  }
  int find(int x) {
    if (par[x] == x) return x;
    return par[x] = find(par[x]);
  }
  void unite(int x, int y) {
    x = find(x), y = find(y);
    if (x == y) return;
    if (rank[x] < rank[y]) swap(x, y);
    par[y] = x;
    size_[x] += size_[y];
    if (rank[x] == rank[y]) rank[x]++;
  }
  bool same(int x, int y) { return find(x) == find(y); }
  int size(int x) { return size_[find(x)]; }
};
template <class T, class Func = function<T(T, T)>>
class segtree {
  vector<T> obj;
  int offset;
  Func updater;
  T e;
  int bufsize(int num) {
    int i = 1;
    for (; num > i; i <<= 1)
      ;
    offset = i - 1;
    return (i << 1) - 1;
  }
  T query(int a, int b, int k, int l, int r) {
    if (r <= a || b <= l) return e;
    if (a <= l && r <= b)
      return obj[k];
    else
      return updater(query(a, b, k * 2 + 1, l, (l + r) / 2),
                     query(a, b, k * 2 + 2, (l + r) / 2, r));
  }

 public:
  T query(int a, int b) { return query(a, b, 0, 0, offset + 1); }
  void updateall(int l = 0, int r = -1) {
    if (r < 0) r = offset + 1;
    l += offset, r += offset;
    if (l == 0) return;
    do {
      l = l - 1 >> 1, r = r - 1 >> 1;
      for (int i = l; i < r; i++)
        obj[i] = updater(obj[i * 2 + 1], obj[i * 2 + 2]);
    } while (l);
  }
  void update(int k, T &a) {
    k += offset;
    obj[k] = a;
    while (k) {
      k = k - 1 >> 1;
      obj[k] = updater(obj[k * 2 + 1], obj[k * 2 + 2]);
    }
  }
  segtree(int n, T e, const Func &updater = Func())
      : obj(bufsize(n), e), e(e), updater(updater) {}
  segtree(vector<T> &vec, T e, const Func &updater = Func())
      : obj(bufsize(vec.size()), e), e(e), updater(updater) {
    copy(vec.begin(), vec.end(), obj.begin() + offset);
    updateall();
  }
  T &operator[](int n) { return obj[n + offset]; }
};
template <class T = int>
class BIT {
  vector<T> bit;

 public:
  BIT(int n) : bit(n + 1, 0) {}
  void add(int i, T x) {
    i++;
    while (i <= bit.size()) {
      bit[i - 1] += x;
      i += i & -i;
    }
  }
  T sum(int i) {
    T s = 0;
    i++;
    while (i) {
      s += bit[i - 1];
      i &= i - 1;
    }
    return s;
  }
};
template <class T>
class rangeadd {
  BIT<T> b0, b1;
  int n;
  rangeadd(int n) : b0(n), b1(n), n(n) {}
  void add(int l, int r, T x) {
    b0.add(l, -x(l - 1));
    b1.add(l, x);
    b0.add(r, x * r);
    b1.add(r, -x);
  }
  T sum(int i) { return b0.sum(i) + b1.sum(i) * i; }
};
class Flow {
  int V;
  struct edge {
    int to, cap, rev, cost, add;
  };
  vector<vector<edge>> G;
  vector<int> level, iter, h, dist, prevv, preve;
  void bfs(int s) {
    fill(level.begin(), level.end(), -1);
    queue<int> que;
    level[s] = 0;
    que.push(s);
    while (!que.empty()) {
      int v = que.front();
      que.pop();
      for (int i = 0; i < G[v].size(); i++) {
        edge &e = G[v][i];
        if (e.cap > 0 && level[e.to] < 0) {
          level[e.to] = level[v] + 1;
          que.push(e.to);
        }
      }
    }
  }
  int dfs(int v, int t, int f) {
    if (v == t) return f;
    for (int &i = iter[v]; i < G[v].size(); i++) {
      edge &e = G[v][i];
      if (e.cap > 0 && level[v] < level[e.to]) {
        int d = dfs(e.to, t, min(f, e.cap));
        if (d > 0) {
          e.cap -= d;
          G[e.to][e.rev].cap += d;
          return d;
        }
      }
    }
    return 0;
  }
  int res = 0;
  int flow = 0;
  int s, t;
  int max_flow(int s, int t, int fmax = numeric_limits<int>::max()) {
    level.resize(V);
    iter.resize(V);
    for (;;) {
      bfs(s);
      if (level[t] < 0) return flow;
      fill(iter.begin(), iter.end(), 0);
      int f;
      while ((f = dfs(s, t, fmax)) > 0) {
        flow += f;
        fmax -= f;
      }
      if (fmax == 0) return flow;
    }
  }
  int min_cost_flow(int s, int t, int f) {
    h.resize(V);
    dist.resize(V);
    prevv.resize(V);
    preve.resize(V);
    fill(h.begin(), h.end(), 0);
    while (f > 0) {
      priority_queue<pair<int, int>, vector<pair<int, int>>,
                     greater<pair<int, int>>>
          que;
      fill(dist.begin(), dist.end(), numeric_limits<int>::max());
      dist[s] = 0;
      que.push({0, s});
      while (!que.empty()) {
        pair<int, int> p = que.top();
        que.pop();
        int v = p.second;
        if (dist[v] < p.first) continue;
        for (int i = 0; i < G[v].size(); i++) {
          edge &e = G[v][i];
          if (e.cap > 0 && dist[e.to] > dist[v] + e.cost + h[v] - h[e.to]) {
            dist[e.to] = dist[v] + e.cost + h[v] - h[e.to];
            prevv[e.to] = v;
            preve[e.to] = i;
            que.push({dist[e.to], e.to});
          }
        }
      }
      if (dist[t] == numeric_limits<int>::max()) {
        return -1;
      }
      for (int v = 0; v < V; v++) h[v] += dist[v];
      int d = f;
      for (int v = t; v != s; v = prevv[v]) {
        d = min(d, G[prevv[v]][preve[v]].cap);
      }
      f -= d;
      res += d * h[t];
      for (int v = t; v != s; v = prevv[v]) {
        edge &e = G[prevv[v]][preve[v]];
        e.cap -= d;
        G[v][e.rev].cap += d;
      }
    }
    return res;
  }

 public:
  Flow(int size, int s, int t) : G(size + 1), V(size + 1), s(s), t(t) {}
  void add_edge(int from, int to, int cap, int cost = 0) {
    G[from].push_back(edge{to, cap, (int)G[to].size(), cost, 1});
    G[to].push_back(edge{from, 0, (int)G[from].size() - 1, -cost, 0});
  }
  void remove_edge_max(int from, int to, int cap, int cost = 0) {
    for (auto &x : G[from]) {
      if (!x.add || x.to != to || x.cap + G[to][x.rev].cap != cap ||
          x.cost != cost)
        continue;
      int prev = flow;
      int cap = G[to][x.rev].cap;
      G[to][x.rev].cap = 0;
      x.cap = 0;
      cap -= max_flow(from, to, cap) - prev;
      max_flow(t, to, cap);
      max_flow(from, s, cap);
      flow = prev - cap;
      break;
    }
  }
  void remove_edge_cost(int from, int to, int cap, int cost = 0) {
    for (auto &x : G[from]) {
      if (!x.add || x.to != to || x.cap + G[to][x.rev].cap != cap ||
          x.cost != cost)
        continue;
      cost += G[to][x.rev].cap * G[to][x.rev].cost;
      int cap = G[to][x.rev].cap;
      G[to][x.rev].cap = 0;
      x.cap = 0;
      min_cost_flow(from, to, cap);
      break;
    }
  }
  int max_flow() { return max_flow(s, t); }
  int min_cost_flow(int f) { return min_cost_flow(s, t, f); }
};
int main() {
  int n, k, q;
  cin >> n >> k >> q;
  vi a(n);
  for (int i = 0; i < n; i++) cin >> a[i];
  auto ax = a;
  sort(ax.begin(), ax.end());
  int res = 1e9;
  for (auto x : ax) {
    int d = 0;
    int ds = 0;
    vi b;
    for (int i = 0; i < n; i++) {
      if (x > a[i]) {
        if (i - d <= k - 1) {
          b.erase(ds + b.begin(), b.end());
        }
        ds = b.size();
        d = i;
      } else
        b.push_back(a[i]);
    }
    if (n - d <= k - 1) b.erase(ds + b.begin(), b.end());
    sort(b.begin(), b.end());
    if (b.size() < q) break;
    cmin(res, b[q - 1] - b[0]);
  }
  cout << res << endl;
}
