title: Cassinis Identity
signature: function cassinis_identity(n)
test_code: using Printf
  
  # SOLUTION CODE
  # ============================================
  PLACEHOLDER_CODE_BODY
  
  # TESTING CODE 
  # ============================================
  function validate_solution(actual, expected)
      return actual == expected
  end
  
  function driver(n, expected)
      try
  
          if validate_solution(PLACEHOLDER_FN_NAME(n), expected)
              return "PASSED";
          end
          return "FAILED";
      catch exception_obj
          return string(Base.typename(typeof(exception_obj)).wrapper);
      end
  end
  
  function main()
      
      result = driver(67, -1);
      @printf("TEST-0...%s\n",result);
      
      result = driver(2, 1);
      @printf("TEST-1...%s\n",result);
      
      result = driver(58, 1);
      @printf("TEST-2...%s\n",result);
      
      result = driver(6, 1);
      @printf("TEST-3...%s\n",result);
      
      result = driver(42, 1);
      @printf("TEST-4...%s\n",result);
      
      result = driver(17, -1);
      @printf("TEST-5...%s\n",result);
      
      result = driver(37, -1);
      @printf("TEST-6...%s\n",result);
      
      result = driver(44, 1);
      @printf("TEST-7...%s\n",result);
      
      result = driver(23, -1);
      @printf("TEST-8...%s\n",result);
      
      result = driver(40, 1);
      @printf("TEST-9...%s\n",result);
      
  end
  
  main()
source_py: def cassinis_identity(n):
      return ((- 1) if (n & 1) else 1)
source_cpp: int cassinis_identity(int n) {
    return ( n & 1 ) ? - 1 : 1;
  }