appends_needed.cpp

// C program to find minimum number of appends 
// needed to make a string Palindrome 
#include<stdio.h> 
#include<string.h> 
#include<stdbool.h> 

// Checking if the string is palindrome or not 
bool isPalindrome(char *str) 
{ 
	int len = strlen(str); 

	// single character is always palindrome 
	if (len == 1) 
		return true; 

	// pointing to first character 
	char *ptr1 = str; 

	// pointing to last character 
	char *ptr2 = str+len-1; 

	while (ptr2 > ptr1) 
	{ 
		if (*ptr1 != *ptr2) 
			return false; 
		ptr1++; 
		ptr2--; 
	} 

	return true; 
} 

// Recursive function to count number of appends 
int noOfAppends(char s[]) 
{ 
	if (isPalindrome(s)) 
		return 0; 

	// Removing first character of string by 
	// incrementing base address pointer. 
	s++; 

	return 1 + noOfAppends(s); 
} 

// Driver program to test above functions 
int main() 
{ 
	char s[] = "abede"; 
	printf("%d\n", noOfAppends(s)); 
	return 0; 
}