title: Number Subsequences Form Ai Bj Ck
signature: def number_subsequences_form_ai_bj_ck(s):
test_code: import array
  import bisect
  import collections
  import datetime
  import functools
  import heapq
  import itertools
  import math
  import queue
  import re
  import string
  import sys
  from typing import Any, Dict, List, Optional, Set
  
  
  # SOLUTION CODE
  # ============================================
  PLACEHOLDER_CODE_BODY
  
  # TESTING CODE 
  # ============================================
  def validate_solution(actual, expected):
      return actual == expected
  
  def driver(s, expected):
      try:
          if validate_solution(PLACEHOLDER_FN_NAME(
              s),
              expected
          ):
              return "PASSED"
          return "FAILED"
      except Exception as exception_obj:
          return type(exception_obj).__name__
      
  if __name__ == "__main__":
      result = driver("", 0)
      print(f"TEST-0...{result}")
  
      result = driver("abbc", 3)
      print(f"TEST-1...{result}")
  
      result = driver("abcabc", 7)
      print(f"TEST-2...{result}")
  
      result = driver("agsdbkfdc ", 1)
      print(f"TEST-3...{result}")
  
      result = driver("ababab", 0)
      print(f"TEST-4...{result}")
  
      result = driver("aaaaaaa", 0)
      print(f"TEST-5...{result}")
  
      result = driver("aabaaabcc", 111)
      print(f"TEST-6...{result}")
  
      result = driver("19", 0)
      print(f"TEST-7...{result}")
  
      result = driver("1001100", 0)
      print(f"TEST-8...{result}")
  
      result = driver("DtAnuQbU", 0)
      print(f"TEST-9...{result}")
  
      sys.exit(0)
source_py: def number_subsequences_form_ai_bj_ck(s):
      aCount = 0
      bCount = 0
      cCount = 0
      for i in range(len(s)):
          if (s[i] == 'a'):
              aCount = (1 + (2 * aCount))
          elif (s[i] == 'b'):
              bCount = (aCount + (2 * bCount))
          elif (s[i] == 'c'):
              cCount = (bCount + (2 * cCount))
      return cCount
source_cpp: int number_subsequences_form_ai_bj_ck(string s) {
    int aCount = 0;
    int bCount = 0;
    int cCount = 0;
    for ( unsigned int i = 0;
    i < s . size ( );
    i ++ ) {
      if ( s [ i ] == 'a' ) aCount = ( 1 + 2 * aCount );
      else if ( s [ i ] == 'b' ) bCount = ( aCount + 2 * bCount );
      else if ( s [ i ] == 'c' ) cCount = ( bCount + 2 * cCount );
    }
    return cCount;
  }