# Python | Check if a given string is binary string or not

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
```

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