Answer:
Here is the answer in Java with appropriate comments for understanding
Explanation:
import java.util.Scanner;
public class Hash {
public static void main(String[] args) {
System.out.print("Enter a string : ");
Scanner scanner = new Scanner(System. in);
String s = scanner. nextLine(); //read string
int k=s.lastIndexOf('#'),count=0;//find last occurence of # then take the next part
String s2="",s3="";
for(int i=0;i<s.length();i++)
{
if(s.charAt(i)=='#')
count++;//count the occurence of # of level of heading h1,h2,h3,....
}
for(int j=k+1;j<s.length();j++)
{
s2+=s.charAt(j);//take the remainging string after #
}
// System.out.println(k);
//System.out.println(count);
if(count<=6)//if it is valid heading
{
s3="<h"+count+">"+s2+"</h"+count+">";
System.out.println(s3);
}
else
System.out.println("Invalid header");
}
}
