How can I get a char array in reverse order?

Question

my assignment question is like that

Write a program which prints the letters in a char array in reverse order using

void printReverse(char letters[], int size);

For example, if the array contains {'c', 's', 'c', '2', '6', '1'} the output should be "162csc".

I tried, but I don't know what it means

void printReverse(char letters[], int size);

I did this but there's a problem with calling the method "printReverse" into the main method

import java.util.Arrays;
import java.util.Collections;
 
public class search {

    public static void main(String[] args) {          
 
        char[] letters = {'e', 'v', 'o', 'l', '4'};
        printReverse();

    }

    public void printReverse(char[] letters, int size) {
    
        for (int i = letters.length-1; i >= 0 ; i--) {
        System.out.print(letters[i]);
    }
}

Solution 1

I believe what you wrote is the signature of the method you have to create.

public void printReverse(char[] letters, int size){
   //code here
}

You would have to iterate the array and print what it contains backwards. Use a reverse "for loop" to go through each item in "letters". I'll let you combine these yourself as it's an assignment. Here's an example of a for loop:

for (int i = array.length-1; i >= 0 ; i--){
    System.out.print(array[i]);
}

Solution 2

You can make use of StringBuilder#reverse() method like this:

String reverse = new StringBuilder(new String(letters)).reverse().toString();

Solution 3

This should take about 6 ms. It reverses a char array "in-place" before printing.

public static void reverseString(char[] s) {
    int len = s.length;

    if (len == 0)
        return;

    for (int i=0; i < (len/2); i++)
    {
        char l = s[i];
        s[i] = s[len-i-1];
        s[len-i-1] = l;
    }

    System.out.println(s);
}

Solution 4

`

//not only prints the reverse order, but creates new char array with chars in desired order
char[] letters = {'e', 'v', 'o', 'l', '4'};
int i = letters.length - 1, j = 0;
char[] let = new char[letters.length];
while(i >= 0){
     let[j] = letters[i];
     i--;
     j++;
}
for (char c : let){
     System.out.print(c);
}

`

output: 4love

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