// C/C++ program to check whether it is possible to make // string palindrome by removing one character #include    using namespace std; // Utility method to check if substring from low to high is // palindrome or not. bool isPalindrome(string::iterator low string::iterator high) {  while (low < high)  {  if (*low != *high)  return false;  low++;  high--;  }  return true; } // This method returns -1 if it is not possible to make string // a palindrome. It returns -2 if string is already a palindrome. // Otherwise it returns index of character whose removal can // make the whole string palindrome. int possiblePalinByRemovingOneChar(string str) {  // Initialize low and high by both the ends of the string  int low = 0 high = str.length() - 1;  // loop until low and high cross each other  while (low < high)  {  // If both characters are equal then move both pointer  // towards end  if (str[low] == str[high])  {  low++;  high--;  }  else  {  /* If removing str[low] makes the whole string palindrome.  We basically check if substring str[low+1..high] is  palindrome or not. */  if (isPalindrome(str.begin() + low + 1 str.begin() + high))  return low;  /* If removing str[high] makes the whole string palindrome  We basically check if substring str[low+1..high] is  palindrome or not. */  if (isPalindrome(str.begin() + low str.begin() + high - 1))  return high;  return -1;  }  }  // We reach here when complete string will be palindrome  // if complete string is palindrome then return mid character  return -2; } // Driver code to test above methods int main() {  string str = 'abecbea';  int idx = possiblePalinByRemovingOneChar(str);  if (idx == -1)  cout << 'Not Possible n';  else if (idx == -2)  cout << 'Possible without removing any character';  else  cout << 'Possible by removing character'  << ' at index ' << idx << 'n';  return 0; } 

// Java program to check whether  // it is possible to make string  // palindrome by removing one character import java.util.*; class GFG  {  // Utility method to check if   // substring from low to high is  // palindrome or not.  static boolean isPalindrome(String str   int low int high)  {  while (low < high)   {  if (str.charAt(low) != str.charAt(high))  return false;  low++;  high--;  }  return true;  }  // This method returns -1 if it is   // not possible to make string a palindrome.   // It returns -2 if string is already   // a palindrome. Otherwise it returns   // index of character whose removal can  // make the whole string palindrome.  static int possiblePalinByRemovingOneChar(String str)  {  // Initialize low and right   // by both the ends of the string  int low = 0 high = str.length() - 1;  // loop until low and  // high cross each other  while (low < high)   {  // If both characters are equal then   // move both pointer towards end  if (str.charAt(low) == str.charAt(high))   {  low++;  high--;  }   else  {  /*  * If removing str[low] makes the   * whole string palindrome. We basically   * check if substring str[low+1..high]  * is palindrome or not.  */  if (isPalindrome(str low + 1 high))  return low;  /*  * If removing str[high] makes the whole string   * palindrome. We basically check if substring   * str[low+1..high] is palindrome or not.  */  if (isPalindrome(str low high - 1))  return high;  return -1;  }  }  // We reach here when complete string   // will be palindrome if complete string   // is palindrome then return mid character  return -2;  }  // Driver Code  public static void main(String[] args)  {  String str = 'abecbea';  int idx = possiblePalinByRemovingOneChar(str);  if (idx == -1)  System.out.println('Not Possible');  else if (idx == -2)  System.out.println('Possible without ' +   'removing any character');  else  System.out.println('Possible by removing' +   ' character at index ' + idx);  } } // This code is contributed by // sanjeev2552 

# Python program to check whether it is possible to make # string palindrome by removing one character # Utility method to check if substring from  # low to high is palindrome or not. def isPalindrome(string: str low: int high: int) -> bool: while low < high: if string[low] != string[high]: return False low += 1 high -= 1 return True # This method returns -1 if it  # is not possible to make string # a palindrome. It returns -2 if  # string is already a palindrome. # Otherwise it returns index of # character whose removal can # make the whole string palindrome. def possiblepalinByRemovingOneChar(string: str) -> int: # Initialize low and right by # both the ends of the string low = 0 high = len(string) - 1 # loop until low and high cross each other while low < high: # If both characters are equal then # move both pointer towards end if string[low] == string[high]: low += 1 high -= 1 else: # If removing str[low] makes the whole string palindrome. # We basically check if substring str[low+1..high] is # palindrome or not. if isPalindrome(string low + 1 high): return low # If removing str[high] makes the whole string palindrome # We basically check if substring str[low+1..high] is # palindrome or not if isPalindrome(string low high - 1): return high return -1 # We reach here when complete string will be palindrome # if complete string is palindrome then return mid character return -2 # Driver Code if __name__ == '__main__': string = 'abecbea' idx = possiblepalinByRemovingOneChar(string) if idx == -1: print('Not possible') else if idx == -2: print('Possible without removing any character') else: print('Possible by removing character at index' idx) # This code is contributed by # sanjeev2552 

// C# program to check whether  // it is possible to make string  // palindrome by removing one character using System; class GFG  {  // Utility method to check if   // substring from low to high is  // palindrome or not.  static bool isPalindrome(string str int low int high)  {  while (low < high)   {  if (str[low] != str[high])  return false;  low++;  high--;  }  return true;  }  // This method returns -1 if it is   // not possible to make string a palindrome.   // It returns -2 if string is already   // a palindrome. Otherwise it returns   // index of character whose removal can  // make the whole string palindrome.  static int possiblePalinByRemovingOneChar(string str)  {  // Initialize low and right   // by both the ends of the string  int low = 0 high = str.Length - 1;  // loop until low and  // high cross each other  while (low < high)   {  // If both characters are equal then   // move both pointer towards end  if (str[low] == str[high])   {  low++;  high--;  }   else  {  /*  * If removing str[low] makes the   * whole string palindrome. We basically   * check if substring str[low+1..high]  * is palindrome or not.  */  if (isPalindrome(str low + 1 high))  return low;  /*  * If removing str[high] makes the whole string   * palindrome. We basically check if substring   * str[low+1..high] is palindrome or not.  */  if (isPalindrome(str low high - 1))  return high;  return -1;  }  }  // We reach here when complete string   // will be palindrome if complete string   // is palindrome then return mid character  return -2;  }  // Driver Code  public static void Main(String[] args)  {  string str = 'abecbea';  int idx = possiblePalinByRemovingOneChar(str);  if (idx == -1)  Console.Write('Not Possible');  else if (idx == -2)  Console.Write('Possible without ' +   'removing any character');  else  Console.Write('Possible by removing' +   ' character at index ' + idx);  } } // This code is contributed by shivanisinghss2110 

<script> // JavaScript program to check whether  // it is possible to make string  // palindrome by removing one character // Utility method to check if  // substring from low to high is // palindrome or not. function isPalindrome(str low high)  {  while (low < high)   {  if (str.charAt(low) != str.charAt(high))  return false;  low++;  high--;  }  return true;  }  // This method returns -1 if it is   // not possible to make string a palindrome.   // It returns -2 if string is already   // a palindrome. Otherwise it returns   // index of character whose removal can  // make the whole string palindrome.  function possiblePalinByRemovingOneChar(str)  {  // Initialize low and right   // by both the ends of the string  var low = 0 high = str.length - 1;  // loop until low and  // high cross each other  while (low < high)   {  // If both characters are equal then   // move both pointer towards end  if (str.charAt(low) == str.charAt(high))   {  low++;  high--;  }   else  {  /*  * If removing str[low] makes the   * whole string palindrome. We basically   * check if substring str[low+1..high]  * is palindrome or not.  */  if (isPalindrome(str low + 1 high))  return low;  /*  * If removing str[high] makes the whole string   * palindrome. We basically check if substring   * str[low+1..high] is palindrome or not.  */  if (isPalindrome(str low high - 1))  return high;  return -1;  }  }  // We reach here when complete string   // will be palindrome if complete string   // is palindrome then return mid character  return -2;  }  // Driver Code  var str = 'abecbea';  var idx = possiblePalinByRemovingOneChar(str);  if (idx == -1)  document.write('Not Possible');  else if (idx == -2)  document.write('Possible without ' +   'removing any character');  else  document.write('Possible by removing' +   ' character at index ' + idx); // this code is contributed by shivanisinghss2110 </script>