Write a program in Java to enter any sentence. Also ask the user to enter a word. Print the number of times the word entered is present in the sentence. If the word is not present in the sentence, then print an appropriate message.

Which of the following returns a String?

1. length()
2. charAt(int)
3. replace(char, char)
4. indexOf(String)

The following code to compare two strings is compiled, the following syntax error was displayed – incompatible types – int cannot be converted to boolean.

Identify the statement which has the error and write the correct statement. Give the output of the program segment.

void calculate()
{
String a = "KING", b = "KINGDOM";
boolean x = a.compareTo(b);
System.out.println(x);
}

Define a class to accept the gmail id and check for its validity.

A gmail id is valid only if it has:

→ @

→ .(dot)

→ gmail

→ com

Example: icse2024@gmail.com is a valid gmail id