Question

2. Write a Java program that generates a new string by concatenating the reversed substrings of even indexes and odd indexes separately from a given string. For this code you may use the above method to reverse the string. [10 points] Example #1 Input: abscacd Output: dasaccb Explanation: Substring are: asad, bcc Reversed substrings are: dasa, ccb Output: dasaccb

Answer 1

1. public class Main {
2. public static void main(String[] args) {
3. String testString = "abscacd";
5. String evenStr = "";
6. String oddStr = "";
8. for(int i=testString.length() - 1; i >= 0; i--){
10. if(i % 2 == 0){
11. evenStr += testString.charAt(i);
12. }
13. else{
14. oddStr += testString.charAt(i);
15. }
16. }
18. System.out.println(evenStr + oddStr);
19. }
20. }

Step-by-step explanation:

Firstly, let declare a variable testString to hold an input string "abscacd" (Line 1).

Next create another two String variable, evenStr and oddStr and initialize them with empty string (Line 5-6). These two variables will be used to hold the string at even index and odd index, respectively.

Next, we create a for loop that traverse the characters of the input string from the back by setting initial position index i to testString.length() - 1 (Line 8). Within the for-loop, create if and else block to check if the current index, i is divisible by 2, (i % 2 == 0), use the current i to get the character of the testString and join it with evenStr. Otherwise, join it with oddStr (Line 10 -14).

At last, we print the concatenated evenStr and oddStr (Line 18).