Count Matching Characters in a Pair of Strings in Python

We are given two strings. We need to find the count it of the characters in the first string which are also present in a second string.

With set

The set function gives us unique values all the elements in a string. We also use the the & operator which finds the common elements between the two given strings.

Example

 Live Demo

strA = 'Tutorials Point'
uniq_strA = set(strA)
# Given String
print("Given String\n",strA)
strB = 'aeio'
uniq_strB = set(strB)
# Given String
print("Search character strings\n",strB)
common_chars = uniq_strA & uniq_strB
print("Count of matching characters are : ",len(common_chars))

Output

Running the above code gives us the following result −

Given String
Tutorials Point
Search character strings
aeio
Count of matching characters are : 3

With re.search

We use the search function from the re module. We use a count variable and keep incrementing it when the search result is true.

Example

 Live Demo

import re
strA = 'Tutorials Point'
# Given String
print("Given String\n",strA)
strB = 'aeio'
# Given String
print("Search character strings\n",strB)
cnt = 0
for i in strA:
   if re.search(i, strB):
      cnt = cnt + 1
print("Count of matching characters are : ",cnt)

Output

Running the above code gives us the following result −

Given String
Tutorials Point
Search character strings
aeio
Count of matching characters are : 5