title: Cassinis Identity
signature: function cassinisIdentity($n) {
test_code: <?php
  
  
  // SOLUTION CODE 
  // ============================================
  PLACEHOLDER_CODE_BODY
  
  // TESTING CODE 
  // ============================================
  function validateSolution($actual, $expected){
      return serialize($actual) == serialize($expected);
  }
  
  function driver($n, $expected){
      try{
        if (validateSolution(PLACEHOLDER_FN_NAME($n), $expected)){
          return "PASSED";
        }
        return "FAILED";
      }
      catch (Exception $exception_obj) {
        return get_class($exception_obj);
      }
  }
  
  function main(){
      printf("TEST-0...%s\n",driver(
        67, 
        -1));
      
      printf("TEST-1...%s\n",driver(
        2, 
        1));
      
      printf("TEST-2...%s\n",driver(
        58, 
        1));
      
      printf("TEST-3...%s\n",driver(
        6, 
        1));
      
      printf("TEST-4...%s\n",driver(
        42, 
        1));
      
      printf("TEST-5...%s\n",driver(
        17, 
        -1));
      
      printf("TEST-6...%s\n",driver(
        37, 
        -1));
      
      printf("TEST-7...%s\n",driver(
        44, 
        1));
      
      printf("TEST-8...%s\n",driver(
        23, 
        -1));
      
      printf("TEST-9...%s\n",driver(
        40, 
        1));
      
  }
  
  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;
  }