#include<bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef pair<ll, ll> pll;
typedef pair<ull, ull> pullull;
typedef pair<ll, int> plli;
typedef pair<int, pii> pipii;
typedef vector<vector<int> > mati;
typedef vector<vector<double> > matd;
typedef vector<ll> vll;
typedef vector<vector<ll>> vvll;
typedef vector<vector<vector<ll>>> vvvll;
typedef vector<bool> vb;
typedef vector<vector<bool>> vvb;
typedef vector<vector<vector<bool>>> vvvb;
typedef vector<pll> vpll;
typedef vector<vpll> vvpll;

#define FOR(i,x,y) for(ll i=(ll)x; i<(ll)y; ++i)
#define REP(i,y) FOR(i, 0, y)
#define RFOR(i,x,y) for(ll i=(ll)x; i>=(ll)y; --i)
#define RREP(i,x) RFOR(i, x, 0)
#define ALL(a) a.begin(), a.end()
#define pb push_back

inline void IN(void){
  return;
}

template <typename First, typename... Rest>
void IN(First& first, Rest&... rest){
  cin >> first;
  IN(rest...);
  return;
}

inline void OUT(void){
  cout << "\n";
  return;
}

template <typename First, typename... Rest>
void OUT(First first, Rest... rest){
  cout << first << " ";
  OUT(rest...);
  return;
}

template <typename T>
void vec_print(vector<T> VEC){
  REP(i, VEC.size()){
    cout << VEC[i] << " ";
  }
  cout << "\n";
};

template <typename T>
void mat_print(vector<vector<T> > MAT){
  REP(i, MAT.size()){
    REP(j, MAT[i].size()){
      cout << MAT[i][j] << " ";
    }
    cout << "\n";
  }
};

template <typename CLASS1, typename CLASS2>
class HOGE{
  public:
    CLASS1 key;
    CLASS2 value;
    HOGE(void){
      return;
    };
    HOGE(CLASS1 key, CLASS2 value){
      this->key = key;
      this->value = value;
    };
    ~HOGE(void){
      return;
    };

    void print(void){
      cout << "key : " << key << ", value : " << value << "\n";
      return;
    };
    
    bool operator==(const HOGE &obj){
      return (this->value == obj.value);
    };
    bool operator<(const HOGE &obj){
      return (this->value < obj.value);
    };
    bool operator>(const HOGE &obj){
      return (this->value > obj.value);
    };
};

template <typename CLASS1, typename CLASS2>
bool operator==(const HOGE<CLASS1, CLASS2> &hoge1, const HOGE<CLASS1, CLASS2> &hoge2){
  return hoge1.value == hoge2.value;
};

template <typename CLASS1, typename CLASS2>
bool operator<(const HOGE<CLASS1, CLASS2> &hoge1, const HOGE<CLASS1, CLASS2> &hoge2){
  return hoge1.value < hoge2.value;
};

template <typename CLASS1, typename CLASS2>
bool operator>(const HOGE<CLASS1, CLASS2> &hoge1, const HOGE<CLASS1, CLASS2> &hoge2){
  return hoge1.value > hoge2.value;
};

constexpr int INF = (1<<30);
constexpr ll INFLL = 1LL<<62;
constexpr long double EPS = 1e-12;
constexpr ll MOD = (ll)((1E+9)+7);

class Segment_Tree{
  private:
    ll n;
    ll n_;
    ll query_type;

  public:
    vector<ll> dat;
    vector<ll> lazy1; //遅延評価 - http://tsutaj.hatenablog.com/entry/2017/03/30/224339
    vector<ll> lazy2; //遅延評価 - http://tsutaj.hatenablog.com/entry/2017/03/30/224339
    vector<bool> lazy1_flag;
    vector<bool> lazy2_flag;
    Segment_Tree(ll n__, ll query_type_=0){
      // For simply, the number of component is set to be power of 2
      // query_type = 0 : min
      // query_type = 1 : max
      // query_type = 2 : sum
      n = 1;
      n_ = n__;
      while(n < n_) n*=2;

      query_type = query_type_;

      lazy1.resize(2*n-1, 0);
      lazy1_flag.resize(2*n-1, false);
      if(query_type==0){
        dat.resize(2*n-1, INFLL);
        lazy2.resize(2*n-1, INFLL);
      }else if(query_type==1){
        dat.resize(2*n-1, -(INFLL-1));
        lazy2.resize(2*n-1, -(INFLL-1));
      }else if(query_type==2){
        dat.resize(2*n-1, 0);
        lazy2.resize(2*n-1, 0);
      }
      lazy2_flag.resize(2*n-1, false);
      return;
    };

    ~Segment_Tree(void){
      return;
    };

    void eval1(ll k, ll l, ll r){
      if(lazy1_flag[k]){
        dat[k] = lazy1[k];

        if(r-l>1){
          if(query_type==0){
            lazy1[2*k+1] = lazy1[k];
            lazy1[2*k+2] = lazy1[k];
          }else if(query_type==1){
            lazy1[2*k+1] = lazy1[k];
            lazy1[2*k+2] = lazy1[k];
          }else if(query_type==2){
            lazy1[2*k+1] = lazy1[k]/2;
            lazy1[2*k+2] = lazy1[k]/2;
          }
        }
        lazy1_flag[2*k+1] = true;
        lazy1_flag[2*k+2] = true;

        lazy1_flag[k] = false;
        if(query_type==0)
          lazy1[k] = INFLL;
        else if(query_type==1)
          lazy1[k] = -(INFLL-1);
        else if(query_type==2)
          lazy1[k] = 0;
      }
    }

    void eval2(ll k, ll l, ll r){
      if(lazy2_flag[k]){
        if(query_type==0)
          dat[k] = min(dat[k], lazy2[k]);
        else if(query_type==1)
          dat[k] = max(dat[k], lazy2[k]);
        else if(query_type==2)
          dat[k] = dat[k]+lazy2[k];

        if(r-l>1){
          if(query_type==0){
            lazy2[2*k+1] = min(lazy2[2*k+1], lazy2[k]);
            lazy2[2*k+2] = min(lazy2[2*k+2], lazy2[k]);
          }else if(query_type==1){
            lazy2[2*k+1] = max(lazy2[2*k+1], lazy2[k]);
            lazy2[2*k+2] = max(lazy2[2*k+2], lazy2[k]);
          }else if(query_type==2){
            lazy2[2*k+1] += lazy2[k] / 2;
            lazy2[2*k+2] += lazy2[k] / 2;
          }
          lazy2_flag[2*k+1] = true;
          lazy2_flag[2*k+2] = true;
        }

        lazy2_flag[k] = false;
        if(query_type==0)
          lazy2[k] = INFLL;
        else if(query_type==1)
          lazy2[k] = -(INFLL-1);
        else if(query_type==2)
          lazy2[k] = 0;
      }
    }

    //k-th value is changed to a
    void update1(ll k, ll a){
      k += n-1;
      dat[k] = a;
      while(k>0){
        k = (k-1)/2;
        if(query_type==0)
          dat[k] = min(dat[k*2+1], dat[k*2+2]);
        else if(query_type==1)
          dat[k] = max(dat[k*2+1], dat[k*2+2]);
        else if(query_type==2)
          dat[k] = dat[k*2+1]+dat[k*2+2];
      }
      return;
    };

    //k-th value is operated of a
    void update2(ll k, ll a){
      k += n-1;
      if(query_type==0)
        dat[k] = min(dat[k], a);
      else if(query_type==1)
        dat[k] = max(dat[k], a);
      else if(query_type==2)
        dat[k] = dat[k]+a;
      while(k>0){
        k = (k-1)/2;
        if(query_type==0)
          dat[k] = min(dat[k*2+1], dat[k*2+2]);
        else if(query_type==1)
          dat[k] = max(dat[k*2+1], dat[k*2+2]);
        else if(query_type==2)
          dat[k] = dat[k*2+1]+dat[k*2+2];
      }
      return;
    };

    //[a,b)の範囲の値をxに変える
    void rangeupdate1(ll a, ll b, ll x, ll k=0, ll l=0, ll r=-1){
      if(r<0) r=n;

      eval1(k,l,r);

      if(r<=a || b<=l){
        return;
      }

      if(a<=l && r<=b){
        if(query_type==0)
          lazy1[k] = x;
        else if(query_type==1)
          lazy1[k] = x;
        else if(query_type==2)
          lazy1[k] = (r-l)*x;
        lazy1_flag[k] = true;
        eval1(k,l,r);
      }else{
        rangeupdate1(a, b, x, 2*k+1, l, (l+r)/2);
        rangeupdate1(a, b, x, 2*k+2, (l+r)/2, r);
        if(query_type==0)
          dat[k] = min(dat[2*k+1], dat[2*k+2]);
        else if(query_type==1)
          dat[k] = max(dat[2*k+1], dat[2*k+2]);
        else if(query_type==2)
          dat[k] = dat[2*k+1] + dat[2*k+2];
      }
      return;
    }

    //[a,b)の範囲に対してxを作用させる
    void rangeupdate2(ll a, ll b, ll x, ll k=0, ll l=0, ll r=-1){
      if(r<0) r=n;

      eval2(k,l,r);

      if(r<=a || b<=l){
        return;
      }

      if(a<=l && r<=b){
        if(query_type==0)
          lazy2[k] = min(lazy2[k], x);
        if(query_type==1)
          lazy2[k] = max(lazy2[k], x);
        if(query_type==2)
          lazy2[k] = lazy2[k] + (r-l)*x;
        lazy2_flag[k] = true;
        eval2(k,l,r);
      }else{
        rangeupdate2(a, b, x, 2*k+1, l, (l+r)/2);
        rangeupdate2(a, b, x, 2*k+2, (l+r)/2, r);
        if(query_type==0)
          dat[k] = min(dat[2*k+1], dat[2*k+2]);
        else if(query_type==1)
          dat[k] = max(dat[2*k+1], dat[2*k+2]);
        else if(query_type==2)
          dat[k] = dat[2*k+1] + dat[2*k+2];
      }
      return;
    }

    // search the minimum of [a, b)
    // Other values are used for simply
    // From outside, call query(a, b, 0, 0, n)
    // k is the node index, 
    // temporary block is [l, r)
    ll query(ll a, ll b, ll k, ll l, ll r){
      //if there are no overlap between [a, b) and [l, r)
      if(r<=a || b<=l){
        if(query_type==0)
          return INFLL;
        else if(query_type==1)
          return -(INFLL-1);
        else if(query_type==2)
          return 0;
      }

      eval1(k,l,r);
      eval2(k,l,r);

      //if [a, b) contains [l, r), return the value of this node
      if(a<=l && r<=b) return dat[k];

      ll vl = query(a, b, k*2+1, l, (l+r)/2);
      ll vr = query(a, b, k*2+2, (l+r)/2, r);
      if(query_type==0)
        return min(vl, vr);
      else if(query_type==1)
        return max(vl, vr);
      else if(query_type==2)
        return vl+vr;
    };

    // search the minimum of [a, b)
    ll query(ll a, ll b){
      if(a<0 || n_<b || a==b){
        fprintf(stderr, "Segment_Tree Search Space Error\n");
        fprintf(stderr, "Desired:\n");
        fprintf(stderr, "%lld <= %lld < %lld <= %lld\n", 0, a, b, n_);
        exit(0);
      }
      return query(a, b, 0, 0, n);
    };
};



ll N, K, Q;
vll A_copy;
vb flag;
vll L_false_pos;
vll R_false_pos;

bool possible(vll& A, ll index){
  ll begin = max((ll)0, index-K+1);
  ll end = min(index,N-K);
  FOR(i,begin,end+1){
    ll min_val = A[i];
    REP(j,K-1){
      min_val = min(min_val, A[i+j+1]);
    }
    if(min_val==A[index]) return true;
  }
  return false;
}

ll search(vll& A, ll index){
  Segment_Tree que(N-1, 2);
  ll pos = 0;
  vpll tmp;
  REP(i,N){
    if(i==index) continue;
    que.update1(pos, 0);
    A_copy[pos] = A[i];
    if(A_copy[pos]>=A[index]){
      flag[pos] = true;
      tmp.pb(make_pair(A_copy[pos], pos));
    }
    else flag[pos] = false;
    pos++;
  }
  sort(ALL(tmp));

  L_false_pos[0] = -1;
  if(!flag[0]) L_false_pos[0] = 0;
  REP(i,N-2){
    L_false_pos[i+1] = L_false_pos[i];
    if(!flag[i+1]) L_false_pos[i+1] = i+1;
  }
  R_false_pos[N-2] = N-1;
  if(!flag[N-2]) R_false_pos[N-2] = N-2;
  RREP(i,N-3){
    R_false_pos[i] = R_false_pos[i+1];
    if(!flag[i]) R_false_pos[i] = i;
  }

  ll count = 0;

  /*
  fprintf(stderr, "search : index:%lld\n", index);
  fprintf(stderr, "\n");
  REP(i,N-1){
    fprintf(stderr, "%lld %lld\n", i, L_false_pos[i]);
  }
  fprintf(stderr, "\n");
  REP(i,N-1){
    fprintf(stderr, "%lld %lld\n", i, R_false_pos[i]);
  }
  fprintf(stderr, "\n");
  REP(i,tmp.size()){
    fprintf(stderr, "%lld %lld %lld\n", i, tmp[i].first, tmp[i].second);
  }
  fprintf(stderr, "\n");
  */

  REP(i,tmp.size()){
    ll pos = tmp[i].second;

    ll left = L_false_pos[pos];
    ll right = R_false_pos[pos];
    ll one_sum = que.query(left+1, right);
    ll range = right-left-1;
    //fprintf(stderr, "%lld %lld %lld\n", range, K, one_sum);
    if(range>=K+one_sum){
      count++;
      if(count==Q-1) return tmp[i].first;
    }
    que.update1(pos, 1);
  }
  return -1;
}

int main(){
  cin.tie(0); // cut the cin and cout (default, std::flush is performed after std::cin)
  ios::sync_with_stdio(false); // cut the iostream and stdio (DON'T endl; BUT "\n";)

  IN(N,K,Q);
  vll A(N);
  A_copy.resize(N-1);
  flag.resize(N-1);
  L_false_pos.resize(N-1);
  R_false_pos.resize(N-1);
  REP(i,N) IN(A[i]);

  if(Q==1){
    OUT(0);
    return 0;
  }

  ll ans = INFLL;
  REP(i,N){
    //fprintf(stderr, "%lld:\n", i);
    if(!possible(A, i)) continue;
    ll Y = A[i];
    ll X = search(A, i); //A[i]より大きいもので最も小さいX
    //fprintf(stderr, "%lld: %lld %lld\n", i, Y, X);
    if(X<0) continue;
    ans = min(ans, X-Y);
  }

  OUT(ans);

  return 0;
}

Measured memory_bytes: 548