title: Count Words Appear Exactly Two Times Array Words
signature: function countWordsAppearExactlyTwoTimesArrayWords(stri, 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(stri, n, expected){
      try{
          if (validateSolution(PLACEHOLDER_FN_NAME(stri, n),expected)){
              return "PASSED";
          }
          return "FAILED";
      } catch (error) {
        return error.name;
      }
      
  }
      
  function main(){
    let result = '';
    result = driver(["hate", "love", "peace", "love", "peace", "hate", "love", "peace", "love", "peace"], 10, 1);
    console.log(`TEST-0...${result}`);
  
    result = driver(["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);
    console.log(`TEST-1...${result}`);
  
    result = driver(["001000100000", "1010", "01011", "11", "011", "1010"], 6, 1);
    console.log(`TEST-2...${result}`);
  
    result = driver(["Om", "Om", "Shankar", "Tripathi", "Tom", "Jerry", "Jerry"], 7, 2);
    console.log(`TEST-3...${result}`);
  
    result = driver(["2", "644", "2", "42484637089", "81578664", "0778"], 6, 1);
    console.log(`TEST-4...${result}`);
  
    result = driver(["001000101", "011010", "1", "101010011", "011010", "01", "10111000101", "0", "1", "00101101", "0", "0"], 12, 2);
    console.log(`TEST-5...${result}`);
  
    result = driver(["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);
    console.log(`TEST-6...${result}`);
  
    result = driver(["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);
    console.log(`TEST-7...${result}`);
  
    result = driver(["00", "0", "00", "0101111010100", "110"], 4, 1);
    console.log(`TEST-8...${result}`);
  
    result = driver(["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);
    console.log(`TEST-9...${result}`);
  
    process.exit(0);
  };
  
  if (require.main === module) {
    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;
  }