text: #define DEBUG 1
  
  /**
   * File    : A.cpp
   * Author  : Kazune Takahashi
   * Created : 5/22/2019, 4:30:59 PM
   * Powered by Visual Studio Code
   */
  
  #include <iostream>
  #include <iomanip>   // << fixed << setprecision(xxx)
  #include <algorithm> // do { } while ( next_permutation(A, A+xxx) ) ;
  #include <vector>
  #include <string> // to_string(nnn) // substr(m, n) // stoi(nnn)
  #include <complex>
  #include <tuple>
  #include <queue>
  #include <stack>
  #include <map> // if (M.find(key) != M.end()) { }
  #include <set>
  #include <functional>
  #include <random> // auto rd = bind(uniform_int_distribution<int>(0, 9), mt19937(10101010));
  #include <chrono> // std::chrono::system_clock::time_point start_time, end_time;
  // start = std::chrono::system_clock::now();
  // double elapsed = std::chrono::duration_cast<std::chrono::milliseconds>(end_time-start_time).count();
  #include <cctype>
  #include <cassert>
  #include <cmath>
  #include <cstdio>
  #include <cstdlib>
  using namespace std;
  
  typedef long long ll;
  
  // const int dx[4] = {1, 0, -1, 0};
  // const int dy[4] = {0, 1, 0, -1};
  
  // const int C = 1e6+10;
  // const ll M = 1000000007;
  
  int A, B, C;
  
  int main()
  {
    cin >> A >> B >> C;
    if ((A < C && C < B) || (B < C && C < A))
    {
      cout << "Yes" << endl;
    }
    else
    {
      cout << "No" << endl;
    }
  }