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# Python | Count K character between consecutive characters

• Last Updated : 26 Mar, 2020

Sometimes, while working with strings, we can have a problem in which we need to check the count of each character between the consecutive character. This type of problem can have application in day-day and web development domain. Lets discuss certain ways in which this task can be performed.

Method #1 : Using loop
This is brute force way in which this task can be performed. In this, we iterate the list counting the K character between each of characters.

 `# Python3 code to demonstrate working of ``# Count K character between consecutive characters``# Using loop`` ` `# initializing string``test_str ``=` `"g...f..g.i..s....b..e....s...t"`` ` `# printing original string``print``(``"The original string is : "` `+` `test_str)`` ` `# initializing K ``K ``=` `'.'`` ` `# Count K character between consecutive characters``# Using loop``count ``=` `0``res ``=` `[]``for` `ele ``in` `test_str:``    ``if` `ele ``=``=` `K:``        ``count ``+``=` `1``    ``else``:``        ``res.append(count)``        ``count ``=` `0``res ``=` `res[``1``:]`` ` `# printing result ``print``(``"List of character count : "` `+` `str``(res)) `
Output :
```The original string is : g...f..g.i..s....b..e....s...t
List of character count : [3, 2, 1, 2, 4, 2, 4, 3]
```

Method #2 : Using list comprehension + `findall()`
This is yet another way in which this problem can be solved. In this, we check for occurring K character using findall() and list comprehension is used to iterate about the string.

 `# Python3 code to demonstrate working of ``# Count K character between consecutive characters``# Using list comprehension + findall()``import` `re`` ` `# initializing string``test_str ``=` `"g---f--g-i--s----b--e----s---t"`` ` `# printing original string``print``(``"The original string is : "` `+` `test_str)`` ` `# Count K character between consecutive characters``# Using list comprehension + findall()``res ``=` `[``len``(ele) ``for` `ele ``in` `re.findall(``'(?<=[a-z])-*(?=[a-z])'``, test_str)]`` ` `# printing result ``print``(``"List of character count : "` `+` `str``(res)) `
Output :
```The original string is : g---f--g-i--s----b--e----s---t
List of character count : [3, 2, 1, 2, 4, 2, 4, 3]```

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