Answer:
import java.util.Scanner;
public class num5 {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
System.out.println("Enter The First String");
String str1 = in.next();
System.out.println("Enter The Second String");
String str2 = in.next();
System.out.println("Enter The Third String");
String str3 = in.next();
String oneAndTwo = str1+str2;
if(str3.equals(oneAndTwo)){
System.out.println(str1+" + "+str2+" is equal to "+str3+"!");
}
else
System.out.println(str1+" + "+str2+" is not equal to "+str3+"!");
}
}
Explanation: