In this post, we will learn Palindrome Program in java Programming language.
Question:
Astrologist believes that having a palindromic name is very auspicious. As we all know, a palindrome is a word that can be read the same way in either direction. There should not be a space or any special character in the word entered. If yes, display “Invalid Input”. Write a Java program to determine whether a given word is a palindrome or not.
Sample Input 1:
Enter the word :
Malayalam
Sample Output 1:
Malayalam is a Palindrome
Sample Input 2:
Enter the word :
Apple
Sample Output 2:
Apple is not a Palindrome
Sample Input 3:
Enter the word :
no on
Sample Output 3:
Invalid Input
Sample Input 4:
Enter the word :
@nnn
Sample Output 4:
Invalid Input
CODE:–
import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Palindrome
{
public static void main (String[] args) {
Scanner sc= new Scanner(System.in);
System.out.println("Enter the word :");
String str=sc.nextLine();
int len=str.length();
Pattern p=Pattern.compile("[^a-z0-9]", Pattern.CASE_INSENSITIVE);
Matcher m=p.matcher(str);
boolean b=m.find();
if(b)
{
System.out.println("Invalid Input");
}
else
{
String rvs=new String();
for(int i=(len-1); i>=0; i--)
{
rvs=rvs+str.charAt(i);
}
if(str.equalsIgnoreCase(rvs))
{
System.out.println(str+" is a Palindrome");
}
else
{
System.out.println(str+" is not a Palindrome");
}
}
}
}public class Student
{
private int id;
private String name;
private int[] marks;
private float average;
private char grade;
public void setId(int id)
{
this.id=id;
}
public int getId()
{
return this.id;
}
public void setName(String name)
{
this.name=name;
}
public String getName()
{
return this.name;
}
public void setMarks(int[] marks)
{
this.marks=marks;
}
public int[] getMarks()
{
return this.marks;
}
public void calculateAvg()
{ float sum=0;
for(int i=0;i<this.marks.length;i++)
{
sum+=this.marks[i];
}
average=(float)(sum/(this.marks.length));
setAverage(average);
}
public void findGrade()
{int flag=0;
for(int i=0;i<this.marks.length;i++)
{
if(this.marks[i]<50)
{
flag++;
}
}
if(flag>0)
{
grade='F';
}
else
{
if(this.average>=80 && this.average<=100)
{
grade='O';
}
else if(this.average>=50 && this.average<=79)
{
grade='A';
}
else
{
grade='F';
}
}
setGrade(grade);
}
public void setAverage(float average)
{
this.average=average;
}
public void setGrade(char grade)
{
this.grade=grade;
}
public float getAverage()
{
return this.average;
}
public char getGrade()
{
return this.grade;
}
}