Question

palindrome is a string that reads the same both forward and backward.

C++

For example, the string "madam" is a palindrome.

Write a program that uses a recursive function to check whether a string is a palindrome.

Your program must contain a value-returning recursive function that returns true if the string is a palindrome and false otherwise. Do not use any global variables; use the appropriate parameters.

Answer 1

Solution.cpp

#include <iostream>//header file for input output function
#include <cstring>//header file for string functions

using namespace std;//it tells the compiler to link std namespace

bool isPalindrome(char *inputString, int leftIndex, int rightIndex);//function declaration

int main(){//main function
    char Str[100];
    cout<<"Enter a string for palindrome check\n";
    cin>> Str;//keyboard inputting
         //calling function
    if(isPalindrome(Str, 0, strlen(Str) - 1)){
        cout<<Str<<" is a Palindrome \n"<< Str;
    } else {
        cout<<Str<<" is not a Palindrome \n"<< Str;
    }
    return 0;
}

/*
* Function to check whether a string is palindrome or not
*/
bool isPalindrome(char *inputString, int leftIndex, int rightIndex){
     /* Input Validation */
     if(NULL == inputString || leftIndex < 0 || rightIndex < 0){
         cout<<"Invalid Input";
         return false;
     }
     /* Recursion termination condition */
     if(leftIndex >= rightIndex)
         return true;
     if(inputString[leftIndex] == inputString[rightIndex]){
         return isPalindrome(inputString, leftIndex + 1,rightIndex - 1);
     }
     return false;
}

output

madam                                                                                                                                                                    

madam is a Palindrome