Write a program to accept a string. Convert the string into upper case letters. Count and output the number of double letter sequences that exist in the string.
Sample Input: "SHE WAS FEEDING THE LITTLE RABBIT WITH AN APPLE"
Sample Output: 4
import java.util.Scanner;
public class KboatLetterSeq
{
public static void main(String args[]) {
Scanner in = new Scanner(System.in);
System.out.print("Enter string: ");
String s = in.nextLine();
String str = s.toUpperCase();
int count = 0;
int len = str.length();
for (int i = 0; i < len - 1; i++) {
if (str.charAt(i) == str.charAt(i + 1))
count++;
}
System.out.println("Double Letter Sequence Count = " + count);
}
}
Enter string: SHE WAS FEEDING THE LITTLE RABBIT WITH AN APPLE
Double Letter Sequence Count = 4
Press any key to continue . . .
First read the algorithm, then study the program code line by line. After that, compare the code with the output and finally go through the explanation. This approach helps learners understand both the logic and the implementation properly.
After understanding this example, try to rewrite the same program without looking at the code. Then change some values or logic and run it again. This helps improve confidence and keeps learners engaged on the page for longer.