Page 427 - Computer science 868 Class 12
P. 427
2. A class called Palword is defined to check if a word is a palindrome or not.
A palindrome is a word which reads same from both ends e.g., NOON, MADAM, MALAYALAM etc. The details of the class is given
below.
Data Members
String w : To store any word
String rw : To store the reverse string
Member Methods
void read() : Accepts any word in upper case
String revword(String x) : Using recursive technique, returns the reverse of the word
void check() : Calls revword (String) and prints if w is a palindrome or not
static void main() : Creates object and calls other methods
Ans. import java.util.*;
class Palword
{ String w,rw;
void read() // input
{ Scanner sc=new Scanner(System.in);
System.out.println("Enter sentence in upper case");
w=sc.next();
rw="";
}
String revword(String x)
{
if(x.equals("")) //base case
return(rw);
else
{
rw=x.charAt(0)+rw; // finding reverse word
return revword(x.substring(1)); //recursive case
}
}
void check()
{ if(revword(w).equals(w)) // checking word=reverse word
System.out.println("Palindrome word "+w); // display
else
System.out.println("Not palindrome word "+w);
}
public static void main()
{ Palword ob=new Palword();
ob.read();
ob.check();
}
}
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Recursion 425

