title: Nth Even Length Palindrome
signature: function nthEvenLengthPalindrome(n) {
test_code: 
  
  // SOLUTION CODE
  // ============================================
  PLACEHOLDER_CODE_BODY
  
  // TESTING CODE 
  // ============================================
  function convertToString(value) {
      return JSON.stringify(value, function (key, val) {
          if (val instanceof Set) {
              return Array.from(val);
          } return val;});
  }
  
  function validateSolution(actual, expected){
      return convertToString(actual)===convertToString(expected);
  }
  
  function driver(n, expected){
      try{
          if (validateSolution(PLACEHOLDER_FN_NAME(n),expected)){
              return "PASSED";
          }
          return "FAILED";
      } catch (error) {
        return error.name;
      }
      
  }
      
  function main(){
    let result = '';
    result = driver("lSUhEvxcgfI", "lSUhEvxcgfIIfgcxvEhUSl");
    console.log(`TEST-0...${result}`);
  
    result = driver("77329283", "7732928338292377");
    console.log(`TEST-1...${result}`);
  
    result = driver("010111111", "010111111111111010");
    console.log(`TEST-2...${result}`);
  
    result = driver("Stazb", "StazbbzatS");
    console.log(`TEST-3...${result}`);
  
    result = driver("0702", "07022070");
    console.log(`TEST-4...${result}`);
  
    result = driver("01111111", "0111111111111110");
    console.log(`TEST-5...${result}`);
  
    result = driver("a", "aa");
    console.log(`TEST-6...${result}`);
  
    result = driver("rznb", "rznbbnzr");
    console.log(`TEST-7...${result}`);
  
    process.exit(0);
  };
  
  if (require.main === module) {
    main();
  }
source_py: def nth_even_length_palindrome(n):
      res = n
      for j in range((len(n) - 1), (- 1), (- 1)):
          res += n[j]
      return res
source_cpp: string nth_even_length_palindrome(string n) {
    string res = n;
    for ( int j = n . length ( ) - 1;
    j >= 0;
    -- j ) res += n [ j ];
    return res;
  }