text: #include <iostream>
  
  using namespace std;
  
  inline
  void use_io_optimizations()
  {
      ios_base::sync_with_stdio(false);
      cin.tie(nullptr);
  }
  
  int main()
  {
      use_io_optimizations();
  
      for (unsigned long long left, right; cin >> left >> right; )
      {
          cout << (left < right ? right - left : left - right) << '\n';
      }
  
      return 0;
  }
  