# Binary String of given length that without a palindrome of size 3

Given an integer n. Find a string of characters ‘a’ and ‘b’ such that the string doesn’t contain any palindrome of length 3.

Examples:

```Input : 3
Output : "aab"
Explanation:
aab is not a palindrome.

Input : 5
Output : aabba
Explanation:
aabba does not contain a palindrome
of size 3.
```

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

The approach here is that we can use this string ‘aabb’ and print the characters of the string according to the given integer.

```We need to make make sure that every third
character is different.

If we perform operation AND on i and 2 where
i = 0 to any positive integer. It will generate
a pattern 0, 0, 2, 2, 0, 0, 2, 2,...
0 AND 2 = 0
1 AND 2 = 0
2 AND 2 = 2
3 AND 2 = 2
4 AND 2 = 0 //repeat the pattern.
```

Below is the code of above approach.

## C++

 `// CPP program find a binary string of  ` `// given length that doesn't contain ` `// a palindrome of size 3. ` `#include ` `using` `namespace` `std; ` ` `  `void` `generatestring(``int` `n) ` `{ ` `    ``// Printing the character according to i ` `    ``for` `(``int` `i = 0; i < n; i++) ` `        ``putchar``(i & 2 ? ``'b'` `: ``'a'``); ` `    ``puts``(``""``); ` `} ` ` `  `// Driver code ` `int` `main() ` `{ ` `    ``int` `n = 5; ` `    ``generatestring(n); ` `    ``n = 8; ` `    ``generatestring(n); ` `    ``n = 10; ` `    ``generatestring(n); ` `} `

## Java

 `// JAVA program find a binary String of  ` `// given length that doesn't contain ` `// a palindrome of size 3. ` ` `  `class` `GFG ` `{ ` ` `  `static` `void` `generateString(``int` `n) ` `{ ` `    ``String s = ``""``; ` `     `  `    ``// Printing the character according to i ` `    ``for` `(``int` `i = ``0``; i < n; i++) ` `        ``s += ((i & ``2``) > ``1` `? ``'b'` `: ``'a'``); ` `    ``System.out.println(s); ` `} ` ` `  `// Driver code ` `public` `static` `void` `main(String[] args) ` `{ ` `    ``int` `n = ``5``; ` `    ``generateString(n); ` `    ``n = ``8``; ` `    ``generateString(n); ` `    ``n = ``10``; ` `    ``generateString(n); ` `} ` `} ` ` `  `// This code is contributed by Rajput-Ji `

## Python3

 `# Python3 program find a binary String of  ` `# given length that doesn't contain ` `# a palindrome of size 3. ` `def` `generateString(n): ` `    ``s ``=` `""; ` `     `  `    ``# Printing the character according to i ` `    ``for` `i ``in` `range``(n): ` `        ``if``((i & ``2``) > ``1``): ` `            ``s ``+``=` `'b'``; ` `        ``else``: ` `            ``s ``+``=` `'a'``; ` `    ``print``(s); ` ` `  `# Driver code ` `if` `__name__ ``=``=` `'__main__'``: ` ` `  `    ``n ``=` `5``; ` `    ``generateString(n); ` `    ``n ``=` `8``; ` `    ``generateString(n); ` `    ``n ``=` `10``; ` `    ``generateString(n); ` ` `  `# This code is contributed by 29AjayKumar `

## C#

 `// C# program find a binary String of  ` `// given length that doesn't contain ` `// a palindrome of size 3. ` `using` `System; ` ` `  `class` `GFG ` `{ ` ` `  `static` `void` `generateString(``int` `n) ` `{ ` `    ``String s = ``""``; ` `     `  `    ``// Printing the character according to i ` `    ``for` `(``int` `i = 0; i < n; i++) ` `        ``s += ((i & 2) > 1 ? ``'b'` `: ``'a'``); ` `    ``Console.WriteLine(s); ` `} ` ` `  `// Driver code ` `public` `static` `void` `Main(String[] args) ` `{ ` `    ``int` `n = 5; ` `    ``generateString(n); ` `    ``n = 8; ` `    ``generateString(n); ` `    ``n = 10; ` `    ``generateString(n); ` `} ` `} ` ` `  `// This code is contributed by Rajput-Ji `

Output:

```
aabba
aabbaabb
aabbaabbaa
```

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Improved By : Rajput-Ji, 29AjayKumar

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