title: Count Words Appear Exactly Two Times Array Words
signature: fun countWordsAppearExactlyTwoTimesArrayWords(stri: ArrayList<String>, n: Int): Int {
test_code: package main
  
  import kotlin.text.*
  import kotlin.math.*
  
  
  // SOLUTION CODE
  // ===================================
  PLACEHOLDER_CODE_BODY
  
  // TESTING CODE
  // ===================================
  fun validateSolution(actual:Int, expected:Int):Boolean{
    return actual.equals(expected)
  }
  fun driver(stri: ArrayList<String>, n: Int, expected:Int):String {
      try{
        if (validateSolution(PLACEHOLDER_FN_NAME(stri, n), expected)) {
                return "PASSED"
        }
        return "FAILED"
      } catch (e: Exception){
        return e::class.simpleName as String
      }
  
  }
  
  fun main() {
      var result: String = ""
      result = driver(arrayListOf("hate", "love", "peace", "love", "peace", "hate", "love", "peace", "love", "peace"), 10, 1)
      println("TEST-0...${result}")
      
      result = driver(arrayListOf("16", "946613197072", "532052", "42780833", "511552", "1241934", "4", "3444540", "47487223670074", "23753", "14158", "4", "95420017116714", "16", "0845", "689000748", "976403809728", "8922", "487784120896", "329", "611", "59101", "611", "2131059721", "53952148295020", "445948587", "3905249775372", "4683180907", "7169093", "01413852276627", "63", "5864", "40862536595", "2280304422294", "930028582", "05", "33447"), 32, 3)
      println("TEST-1...${result}")
      
      result = driver(arrayListOf("001000100000", "1010", "01011", "11", "011", "1010"), 6, 1)
      println("TEST-2...${result}")
      
      result = driver(arrayListOf("Om", "Om", "Shankar", "Tripathi", "Tom", "Jerry", "Jerry"), 7, 2)
      println("TEST-3...${result}")
      
      result = driver(arrayListOf("2", "644", "2", "42484637089", "81578664", "0778"), 6, 1)
      println("TEST-4...${result}")
      
      result = driver(arrayListOf("001000101", "011010", "1", "101010011", "011010", "01", "10111000101", "0", "1", "00101101", "0", "0"), 12, 2)
      println("TEST-5...${result}")
      
      result = driver(arrayListOf("kl", "p sH", "PwCPMPu", "tQoIgPpk", "wtsNP WjS", "kl ", "TXsFWgU", "kl", "AD", "NjjTyFGwNWZcB", "jpFQslbGbDI", "cEpGAgvpk", "EMaDkMOm", "YZuNZgfwDIjG", "k", "hJx jHmGpQYwQP", "CIETe", "RH", "Pj", "h", "DInR", "AEsqOvliQtz", "NwzHTALTt LS", "LwLR", "WvDCzlQF", "soJb", "WktoldCbWyTO", "pIdRJxY", "BmpWxjOwTXkjjL", "zmtCiQ", "g", "yBmDW", "QhaBZrQnOJaAJ", "u", "MGTwCKve", "UxYQrONag", "xsGSz", "dqNPTT", "U W", "ygJKvCEKDClby", "M", "yXJQHxjyDQDLkT", "oJmaREOEk YA", "zUwiwhSMdiC", "jYgZEktcdgLD", "fwyTAAW", "GENttdzeGY "), 43, 1)
      println("TEST-6...${result}")
      
      result = driver(arrayListOf("938", "074209", "0949093096", "218622476", "71692175", "0714", "81217924991", "74016430795374", "52213147", "338", "939", "798161500954", "90528060774015", "68715", "75810", "43450", "8017", "0193164", "5945740", "212", "4589289", "2912211026", "0", "49", "8230114", "0733435391403", "5429", "10070"), 20, 0)
      println("TEST-7...${result}")
      
      result = driver(arrayListOf("00", "0", "00", "0101111010100", "110"), 4, 1)
      println("TEST-8...${result}")
      
      result = driver(arrayListOf("g", "h", "ok", "h", "ok", "sqozuC", "ut", "ZwRcG", "ok", "MR", "jHrWyy", "qaJlrokgRHuZH", "LjPNzDUKszYmCq", "g", "ZGjLfMnyAGL", "kEZoSxOMEWSFpw", "IFtqNaDVnG", "iJoJXl", "vjrQMyWor", "FTEHZqbHGlmHph", "QeSdzm", "nPostKHkigyJt", "mOSekk"), 15, 2)
      println("TEST-9...${result}")
      
          
  }
  
  main()
source_py: def count_words_appear_exactly_two_times_array_words(stri, n):
      m = dict()
      for i in range(n):
          m[stri[i]] = (m.get(stri[i], 0) + 1)
      res = 0
      for i in m.values():
          if (i == 2):
              res += 1
      return res
source_cpp: int count_words_appear_exactly_two_times_array_words(vector<string> str, int n) {
    unordered_map < string, int > m;
    for ( int i = 0;
    i < n;
    i ++ ) m [ str [ i ] ] += 1;
    int res = 0;
    for ( auto it = m . begin ( );
    it != m . end ( );
    it ++ ) if ( ( it -> second == 2 ) ) res ++;
    return res;
  }