Related Articles
Python | Check if a given string is binary string or not
• Difficulty Level : Basic
• Last Updated : 05 Dec, 2019

Given a string str. The task is to check whether it is a binary string or not.

Examples:

```Input: str = "01010101010"
Output: Yes

Input: str = "geeks101"
Output: No
```

## Recommended: Please try your approach on {IDE} first, before moving on to the solution.

Approach 1: Using Set

1. Insert the given string in a set
2. Check if the set characters consist of 1 and/or 0 only.
 `# Python program to check``# if a string is binary or not`` ` `# function for checking the``# string is accepted or not``def` `check(string) :`` ` `    ``# set function convert string``    ``# into set of characters .``    ``p ``=` `set``(string)`` ` `    ``# declare set of '0', '1' .``    ``s ``=` `{``'0'``, ``'1'``}`` ` `    ``# check set p is same as set s``    ``# or set p contains only '0'``    ``# or set p contains only '1'``    ``# or not, if any one condition``    ``# is true then string is accepted``    ``# otherwise not .``    ``if` `s ``=``=` `p ``or` `p ``=``=` `{``'0'``} ``or` `p ``=``=` `{``'1'``}:``        ``print``(``"Yes"``)``    ``else` `:``        ``print``(``"No"``)`` ` ` ` `         ` `# driver code``if` `__name__ ``=``=` `"__main__"` `:`` ` `    ``string ``=` `"101010000111"`` ` `    ``# function calling``    ``check(string)`
Output:
```Yes
```

Approach 2: Simple Iteration

1. Iterate for every character and check if the character is 0 or 1.
2. If it is not then set a counter and break.
3. After iteration check whether the counter is set or not.
 `# Python program to check``# if a string is binary or not`` ` `# function for checking the``# string is accepted or not``def` `check2(string) :`` ` `    ``# initialize the variable t``    ``# with '01' string``    ``t ``=` `'01'`` ` `    ``# initialize the variable count``    ``# with 0 value``    ``count ``=` `0`` ` `    ``# looping through each character``    ``# of the string .``    ``for` `char ``in` `string :`` ` `        ``# check the character is present in``        ``# string t or not.``        ``# if this condition is true``        ``# assign 1 to the count variable``        ``# and break out of the for loop``        ``# otherwise pass``        ``if` `char ``not` `in` `t :``            ``count ``=` `1``            ``break``        ``else` `:``            ``pass``         ` `    ``# after coming out of the loop``    ``# check value of count is non-zero or not``    ``# if the value is non-zero the en condition is true``    ``# and string is not accepted``    ``# otherwise string is accepted``    ``if` `count :``        ``print``(``"No"``)``    ``else` `:``        ``print``(``"Yes"``)`` ` ` ` ` ` `# driver code``if` `__name__ ``=``=` `"__main__"` `:`` ` `    ``string ``=` `"001021010001010"`` ` `    ``# function calling``    ``check2(string)`
Output:
```No
```

Attention geek! Strengthen your foundations with the Python Programming Foundation Course and learn the basics.

To begin with, your interview preparations Enhance your Data Structures concepts with the Python DS Course. And to begin with your Machine Learning Journey, join the Machine Learning – Basic Level Course

My Personal Notes arrow_drop_up