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# Python3 code to demonstrate 
# occurrence frequency using 
# naive method 
  
# initializing string 
test_str = "backendbaz"
  
# using naive method to get count 
# counting a 
count = 0
  
for i in test_str:
    if i == 'a':
        count = count + 1
  
# printing result 
print ("Count of a in backendbaz is : "
                            +  str(count))
# Python3 code to demonstrate 
# occurrence frequency using 
# naive method 
  
# initializing string 
test_str = "backendbaz"
  
# using naive method to get count 
# counting a 
count = 0
  
for i in test_str:
    if i == 'a':
        count = count + 1
  
# printing result 
print ("Count of a in backendbaz is : "
                            +  str(count))اجرای کد

# Python3 code to demonstrate 
# occurrence frequency using 
# count()
  
# initializing string 
test_str = "backendbaz"
  
# using count() to get count 
# counting a 
counter = test_str.count('a')
  
# printing result 
print ("Count of a in backendbaz is : "
                           +  str(counter))
# Python3 code to demonstrate 
# occurrence frequency using 
# count()
  
# initializing string 
test_str = "backendbaz"
  
# using count() to get count 
# counting a 
counter = test_str.count('a')
  
# printing result 
print ("Count of a in backendbaz is : "
                           +  str(counter))اجرای کد

# Python3 code to demonstrate 
# occurrence frequency using 
# collections.Counter()
from collections import Counter
  
# initializing string 
test_str = "backendbaz"
  
# using collections.Counter() to get count 
# counting a 
count = Counter(test_str)
  
# printing result 
print ("Count of a in backendbaz is : "
                       +  str(count['a']))
# Python3 code to demonstrate 
# occurrence frequency using 
# collections.Counter()
from collections import Counter
  
# initializing string 
test_str = "backendbaz"
  
# using collections.Counter() to get count 
# counting a 
count = Counter(test_str)
  
# printing result 
print ("Count of a in backendbaz is : "
                       +  str(count['a']))اجرای کد

# Python3 code to demonstrate 
# occurrence frequency using 
# lambda + sum() + map()
  
# initializing string 
test_str = "backendbaz"
  
# using lambda + sum() + map() to get count 
# counting a 
count = sum(map(lambda x : 1 if 'e' in x else 0, test_str))
  
# printing result 
print ("Count of a in backendbaz is : "
                            +  str(count))
# Python3 code to demonstrate 
# occurrence frequency using 
# lambda + sum() + map()
  
# initializing string 
test_str = "backendbaz"
  
# using lambda + sum() + map() to get count 
# counting a 
count = sum(map(lambda x : 1 if 'e' in x else 0, test_str))
  
# printing result 
print ("Count of a in backendbaz is : "
                            +  str(count))اجرای کد

# Python3 code to demonstrate 
# occurrence frequency using 
# re + findall()
import re
  
# initializing string 
test_str = "backendbaz"
  
# using re + findall() to get count 
# counting a 
count = len(re.findall("e", test_str))
  
# printing result 
print ("Count of a in backendbaz is : "
                            +  str(count))
# Python3 code to demonstrate 
# occurrence frequency using 
# re + findall()
import re
  
# initializing string 
test_str = "backendbaz"
  
# using re + findall() to get count 
# counting a 
count = len(re.findall("e", test_str))
  
# printing result 
print ("Count of a in backendbaz is : "
                            +  str(count))اجرای کد