title: Count Of Occurrences Of A 101 Pattern In A String
signature: function countOfOccurrencesOfA101PatternInAString($s) {
test_code: <?php
  
  
  // SOLUTION CODE 
  // ============================================
  PLACEHOLDER_CODE_BODY
  
  // TESTING CODE 
  // ============================================
  function validateSolution($actual, $expected){
      return serialize($actual) == serialize($expected);
  }
  
  function driver($s, $expected){
      try{
        if (validateSolution(PLACEHOLDER_FN_NAME($s), $expected)){
          return "PASSED";
        }
        return "FAILED";
      }
      catch (Exception $exception_obj) {
        return get_class($exception_obj);
      }
  }
  
  function main(){
      printf("TEST-0...%s\n",driver(
        "1001ab010abc01001", 
        2));
      
      printf("TEST-1...%s\n",driver(
        "1001010001", 
        3));
      
      printf("TEST-2...%s\n",driver(
        "010100010100", 
        3));
      
      printf("TEST-3...%s\n",driver(
        "DLCu", 
        0));
      
      printf("TEST-4...%s\n",driver(
        "7072430592", 
        0));
      
      printf("TEST-5...%s\n",driver(
        "011", 
        0));
      
      printf("TEST-6...%s\n",driver(
        "pnJpypYOza", 
        0));
      
      printf("TEST-7...%s\n",driver(
        "1037", 
        0));
      
      printf("TEST-8...%s\n",driver(
        "111", 
        0));
      
      printf("TEST-9...%s\n",driver(
        "HxK", 
        0));
      
  }
  
  main();
  ?>
source_py: def count_of_occurrences_of_a_101_pattern_in_a_string(s):
      length = len(s)
      oneSeen = False
      count = 0
      for i in range(length):
          if ((s[i] == '1') and oneSeen):
              if (s[(i - 1)] == '0'):
                  count += 1
          if ((s[i] == '1') and (oneSeen == 0)):
              oneSeen = True
          if ((s[i] != '0') and (s[i] != '1')):
              oneSeen = False
      return count
source_cpp: int count_of_occurrences_of_a_101_pattern_in_a_string(string str) {
    int len = str . size ( );
    bool oneSeen = 0;
    int count = 0;
    for ( int i = 0;
    i < len;
    i ++ ) {
      if ( str [ i ] == '1' && oneSeen == 1 ) if ( str [ i - 1 ] == '0' ) count ++;
      if ( str [ i ] == '1' && oneSeen == 0 ) {
        oneSeen = 1;
        continue;
      }
      if ( str [ i ] != '0' && str [ i ] != '1' ) oneSeen = 0;
    }
    return count;
  }