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# Python – Check if string contains any number

In this article, we will check How to check if a string contains a number in Python, we are given a string and we have to return a Boolean result i.e. True or False stating that whether a digit is present in the string or not.

Input : test_str = ‘geeks4g2eeks’
Output : True

Input : test_str = ‘geeksforgeeks’
Output : False

### Check if string contains any number using any() + isdigit()

The combination of the above functions can be used to solve this problem. In this, we check for numbers using isdigit() and check for any occurrence using any().

## Python3

 `# Python3 code to demonstrate working of``# Check if string contains any number``# Using isdigit() + any()` `# initializing string``test_str ``=` `'geeks4geeks'` `# printing original string``print``(``"The original string is : "` `+` `str``(test_str))` `# using any() to check for any occurrence``res ``=` `any``(``chr``.isdigit() ``for` `chr` `in` `test_str)``    ` `# printing result``print``(``"Does string contain any digit ? : "` `+` `str``(res))`

Output

```The original string is : geeks4geeks
Does string contain any digit ? : True```

Time Complexity: O(n)

Auxiliary Space: O(1)

## Check if string contains any number using next() + generator expression + isdigit()

This is yet another way in which this task can be performed. This is recommended in cases of larger strings, the iteration in the generator is cheap, but construction is usually inefficient.

## Python3

 `# Python3 code to demonstrate working of``# Check if string contains any number``# Using isdigit() + next() + generator expression` `# initializing string``test_str ``=` `'geeks4geeks'` `# printing original string``print``(``"The original string is : "` `+` `str``(test_str))` `# next() checking for each element, reaches end, if no element found as digit``res ``=` `True` `if` `next``((``chr` `for` `chr` `in` `test_str ``if` `chr``.isdigit()), ``None``) ``else` `False` `# printing result``print``(``"Does string contain any digit ? : "` `+` `str``(res))`

Output

```The original string is : geeks4geeks
Does string contain any digit ? : True```

Time Complexity: O(n)
Auxiliary Space: O(1)

## Check if string contains any number using the map() function

In this example, we will see if the string contains any number or not using the map function in Python. The map() function returns a map object(which is an iterator) of the results after applying the given function to each item of a given iterable.

## Python3

 `str1 ``=` `"Geeks"``str2 ``=` `"for345"``str3 ``=` `"Geeks"` `print``(``any``(``map``(``str``.isdigit, str1)))``print``(``any``(``map``(``str``.isdigit, str2)))``print``(``any``(``map``(``str``.isdigit, str3)))`

Output

```False
True
False```

Time Complexity: O(n)
Auxiliary Space: O(1)

## Check if string contains any number using re.search(r’\d’)

In this example, we will use the regular expression to check if the string contains the digit or not. A regular expression is a powerful tool for matching text, based on a pre-defined pattern. To check the digit, regular expression use \d which matches the digit character.

## Python3

 `import` `re` `str1 ``=` `"Geek3s"``str2 ``=` `"for345"``str3 ``=` `"Geeks"` `print``(``bool``(re.search(r``'\d'``, str1)))``print``(``bool``(re.search(r``'\d'``, str2)))``print``(``bool``(re.search(r``'\d'``, str3)))`

Output

```True
True
False```

Time Complexity: O(n)
Auxiliary Space: O(1)

## Check if string contains any number using the ASCII code

Here we are iterating over the entire string and comparing each character with the given range of ASCII values and finding if the character is a digit or not.

## Python3

 `def` `digit(s):``    ``for` `i ``in` `s:``        ``if` `ord``(i)>``=``48` `and` `ord``(i)<``=``57``:``            ``return` `True``    ``return` `False``print``(digit(``"Geeks4Geeks"``))``print``(digit(``"GeeksForGeeks"``))`

Output

```True
False```

Time Complexity: O(n)
Auxiliary Space: O(1)

## Python3

 `# Python3 code to demonstrate working of``# Check if string contains any number` `# initializing string``test_str ``=` `'geeks4geeks'` `# printing original string``print``(``"The original string is : "` `+` `str``(test_str))``res``=``False``numbers``=``"0123456789"``for` `i ``in` `test_str:``    ``if` `i ``in` `numbers:``        ``res``=``True``        ``break` `# printing result``print``(``"Does string contain any digit ? : "` `+` `str``(res))`

Output

```The original string is : geeks4geeks
Does string contain any digit ? : True```

Time Complexity: O(n)
Auxiliary Space: O(1)

## Python3

 `# Python3 code to demonstrate working of``# Check if string contains any number` `# initializing string``test_str ``=` `'geeks21geeks'` `# printing original string``print``(``"The original string is : "` `+` `str``(test_str))``res ``=` `False``x ``=` `test_str``numbers ``=` `"0123456789"``for` `i ``in` `numbers:``    ``test_str ``=` `test_str.replace(i, "")``if``(``len``(x) !``=` `len``(test_str)):``    ``res ``=` `True``# printing result``print``(``"Does string contain any digit ? : "` `+` `str``(res))`

Output

```The original string is : geeks21geeks
Does string contain any digit ? : True```

## Python3

 `# Python3 code to demonstrate working of``# Check if string contains any number` `#defining function to check is number present in string or not using find() and any() methods``def` `contains_number(string):``    ``return` `any``(string.find(``str``(i)) ``for` `i ``in` `range``(``10``))` `# initializing string``test_str ``=` `'geeks21geeks'` `# printing original string``print``(``"The original string is : "` `+` `str``(test_str))` `#calling contains_number function``res``=``contains_number(test_str)` `# printing result``print``(``"Does string contain any digit ? : "` `+` `str``(res))`

Output

```The original string is : geeks21geeks
Does string contain any digit ? : True```

## Python3

 `# Python3 code to demonstrate working of``# Check if string contains any number``import` `operator as op``# initializing string``test_str ``=` `'geeks4geeks'` `# printing original string``print``(``"The original string is : "` `+` `str``(test_str))``res ``=` `False``digits ``=` `"0123456789"``for` `i ``in` `test_str:``    ``if` `op.countOf(digits, i) > ``0``:``        ``res ``=` `True``        ``break` `# printing result``print``(``"Does string contain any digit ? : "` `+` `str``(res))`

Output

```The original string is : geeks4geeks
Does string contain any digit ? : True```

Time Complexity: O(n)

Auxiliary Space: O(1)

## Python3

 `# Python3 code to demonstrate working of``# Check if string contains any number` `# initializing string``test_str ``=` `'geeks4geeks'` `# printing original string``print``(``"The original string is : "` `+` `str``(test_str))``res``=``False``for` `i ``in` `test_str:``    ``try``:``      ``int``(i)``      ``res``=``True``      ``break``    ``except``:``      ``res``=``False``# printing result``print``(``"Does string contain any digit ? : "` `+` `str``(res))``#this code contributed by tvsk`

Output

```The original string is : geeks4geeks
Does string contain any digit ? : True```

Time Complexity: O(n)

Auxiliary Space: O(1)

### Another method : Using list and loop

Approach:

1. Declare a characters list numbers consisting numbers from 0 to 9 as shown in code below.
2. Declare ans name variable with False initially.
3. Iterate the given string with loop.
4. If the character is in numbers list then change ans to True and break the loop.
5. After the loop ends, print the ans.

## Python3

 `# Python3 code to demonstrate working of``# Check if string contains any number` `# initializing string``test_str ``=` `'geeks4geeks'` `# printing original string``print``(``"The original string is : "` `+` `str``(test_str))` `ans ``=` `False``numbers ``=` `[``'0'``,``'1'``,``'2'``,``'3'``,``'4'``,``'5'``,``'6'``,``'7'``,``'8'``,``'9'``]` `for` `i ``in` `test_str:``    ``if` `i ``in` `numbers:``        ``ans ``=` `True``        ``break` `# printing result``print``(``"Does string contain any digit ? : "` `, ans)` `# This code is contributed by Pratik Gupta (guptapratik)`

Output

```The original string is : geeks4geeks
Does string contain any digit ? :  True```

Time Complexity: O(n), where n is number of characters in string.

Auxiliary Space: O(1)

My Personal Notes arrow_drop_up