# Recursive function to check if a string is palindrome

Given a string, write a recursive function that check if the given string is palindrome, else not palindrome.

Examples :

```Input : malayalam
Output : Yes
Reverse of malayalam is also
malayalam.

Input : max
Output : No
Reverse of max is not max.
```

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

We have discussed an iterative function here.

The idea of recursive function is simple :

```1) If there is only one character in string
return true.
2) Else compare first and last characters
and recur for remaining substring.
```

Below is the implementation of above idea :

## C

 `// A recursive C program to  ` `// check whether a given number ` `// is palindrome or not ` `#include ` `#include ` `#include ` ` `  `// A recursive function that ` `// check a str[s..e] is ` `// palindrome or not. ` `bool` `isPalRec(``char` `str[],  ` `              ``int` `s, ``int` `e) ` `{ ` `    ``// If there is only one character ` `    ``if` `(s == e) ` `    ``return` `true``; ` ` `  `    ``// If first and last ` `    ``// characters do not match ` `    ``if` `(str[s] != str[e]) ` `    ``return` `false``; ` ` `  `    ``// If there are more than  ` `    ``// two characters, check if  ` `    ``// middle substring is also  ` `    ``// palindrome or not. ` `    ``if` `(s < e + 1) ` `    ``return` `isPalRec(str, s + 1, e - 1); ` ` `  `    ``return` `true``; ` `} ` ` `  `bool` `isPalindrome(``char` `str[]) ` `{ ` `int` `n = ``strlen``(str); ` ` `  `// An empty string is  ` `// considered as palindrome ` `if` `(n == 0) ` `    ``return` `true``; ` ` `  `return` `isPalRec(str, 0, n - 1); ` `} ` ` `  `// Driver Code ` `int` `main() ` `{ ` `    ``char` `str[] = ``"geeg"``; ` ` `  `    ``if` `(isPalindrome(str)) ` `    ``printf``(``"Yes"``); ` `    ``else` `    ``printf``(``"No"``); ` ` `  `    ``return` `0; ` `} `

## Java

 `// A recursive JAVA program to  ` `// check whether a given String  ` `// is palindrome or not ` `import` `java.io.*; ` ` `  `class` `GFG ` `{ ` `    ``// A recursive function that  ` `    ``// check a str(s..e) is  ` `    ``// palindrome or not. ` `    ``static` `boolean` `isPalRec(String str,  ` `                            ``int` `s, ``int` `e) ` `    ``{ ` `        ``// If there is only one character ` `        ``if` `(s == e) ` `            ``return` `true``; ` ` `  `        ``// If first and last  ` `        ``// characters do not match ` `        ``if` `((str.charAt(s)) != (str.charAt(e))) ` `            ``return` `false``; ` ` `  `        ``// If there are more than  ` `        ``// two characters, check if ` `        ``// middle substring is also ` `        ``// palindrome or not. ` `        ``if` `(s < e + ``1``) ` `            ``return` `isPalRec(str, s + ``1``, e - ``1``); ` ` `  `        ``return` `true``; ` `    ``} ` ` `  `    ``static` `boolean` `isPalindrome(String str) ` `    ``{ ` `        ``int` `n = str.length(); ` ` `  `    ``// An empty string is  ` `    ``// considered as palindrome ` `        ``if` `(n == ``0``) ` `            ``return` `true``; ` ` `  `        ``return` `isPalRec(str, ``0``, n - ``1``); ` `    ``} ` ` `  `    ``// Driver Code ` `    ``public` `static` `void` `main(String args[]) ` `    ``{ ` `        ``String str = ``"geeg"``; ` ` `  `        ``if` `(isPalindrome(str)) ` `            ``System.out.println(``"Yes"``); ` `        ``else` `            ``System.out.println(``"No"``); ` `    ``} ` `} ` ` `  `// This code is contributed ` `// by Nikita Tiwari `

## Python

 `# A recursive Python program  ` `# to check whether a given  ` `# number is palindrome or not ` ` `  `# A recursive function that  ` `# check a str[s..e] is  ` `# palindrome or not. ` `def` `isPalRec(st, s, e) : ` `     `  `    ``# If there is only one character ` `    ``if` `(s ``=``=` `e): ` `        ``return` `True` ` `  `    ``# If first and last ` `    ``# characters do not match ` `    ``if` `(st[s] !``=` `st[e]) : ` `        ``return` `False` ` `  `    ``# If there are more than  ` `    ``# two characters, check if  ` `    ``# middle substring is also  ` `    ``# palindrome or not. ` `    ``if` `(s < e ``+` `1``) : ` `        ``return` `isPalRec(st, s ``+` `1``, e ``-` `1``); ` ` `  `    ``return` `True` ` `  `def` `isPalindrome(st) : ` `    ``n ``=` `len``(st) ` `     `  `    ``# An empty string is  ` `    ``# considered as palindrome ` `    ``if` `(n ``=``=` `0``) : ` `        ``return` `True` `     `  `    ``return` `isPalRec(st, ``0``, n ``-` `1``); ` ` `  ` `  `# Driver Code ` `st ``=` `"geeg"` `if` `(isPalindrome(st)) : ` `    ``print` `"Yes"` `else` `: ` `    ``print` `"No"` `     `  `# This code is contributed ` `# by Nikita Tiwari. `

## C#

 `// A recursive C# program to  ` `// check whether a given number ` `// is palindrome or not ` `using` `System; ` ` `  `class` `GFG ` `{ ` ` `  `    ``// A recursive function that  ` `    ``// check a str(s..e) ` `    ``// is palindrome or not. ` `    ``static` `bool` `isPalRec(String str,  ` `                         ``int` `s,  ` `                         ``int` `e) ` `    ``{ ` `         `  `        ``// If there is only one character ` `        ``if` `(s == e) ` `            ``return` `true``; ` ` `  `        ``// If first and last character ` `        ``// do not match ` `        ``if` `((str[s]) != (str[e])) ` `            ``return` `false``; ` ` `  `        ``// If there are more than two ` `        ``// characters, check if middle ` `        ``// substring is also ` `        ``// palindrome or not. ` `        ``if` `(s < e + 1) ` `            ``return` `isPalRec(str, s + 1,  ` `                            ``e - 1); ` `             ``return` `true``; ` `    ``} ` ` `  `    ``static` `bool` `isPalindrome(String str) ` `    ``{ ` `        ``int` `n = str.Length; ` ` `  `        ``// An empty string is considered  ` `        ``// as palindrome ` `        ``if` `(n == 0) ` `            ``return` `true``; ` ` `  `        ``return` `isPalRec(str, 0, n - 1); ` `    ``} ` ` `  `    ``// Driver Code ` `    ``public` `static` `void` `Main() ` `    ``{ ` `        ``String str = ``"geeg"``; ` ` `  `        ``if` `(isPalindrome(str)) ` `            ``Console.Write(``"Yes"``); ` `        ``else` `            ``Console.Write(``"No"``); ` `    ``} ` `} ` ` `  `// This code is contributed by Nitin Mittal. `

## PHP

 ` `

Output :

```Yes
```

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Improved By : nitin mittal

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