You say you want to know the most efficient way and you don't want to know some standard built-in way of doing this. Then I say to you: RTSL (read the source, luke):
Check out the source code for AbstractStringBuilder#reverse, which gets called by StringBuilder#reverse. I bet it does some stuff that you would not have considered for a robust reverse operation.
You say you want to know the most efficient way and you don't want to know some standard built-in way of doing this. Then I say to you: RTSL (read the source, luke):
Check out the source code for AbstractStringBuilder#reverse, which gets called by StringBuilder#reverse. I bet it does some stuff that you would not have considered for a robust reverse operation.
The following does not deal with UTF-16 surrogate pairs.
Copypublic static String reverse(String orig)
{
char[] s = orig.toCharArray();
int n = s.length;
int halfLength = n / 2;
for (int i=0; i<halfLength; i++)
{
char temp = s[i];
s[i] = s[n-1-i];
s[n-1-i] = temp;
}
return new String(s);
}
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You can use this:
new StringBuilder(hi).reverse().toString()
StringBuilder was added in Java 5. For versions prior to Java 5, the StringBuffer class can be used instead — it has the same API.
For Online Judges problems that does not allow StringBuilder or StringBuffer, you can do it in place using char[] as following:
public static String reverse(String input){
char[] in = input.toCharArray();
int begin=0;
int end=in.length-1;
char temp;
while(end>begin){
temp = in[begin];
in[begin]=in[end];
in[end] = temp;
end--;
begin++;
}
return new String(in);
}
hey guys i need your help in java so i have a very beginner problem and i'll probably be laughed at for asking this but how do you reverse a string in java
so far the online called I've been given to work with is:
import java.util.Scanner;
public class Program
{
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
String text = scanner.nextLine();
char[] arr = text.toCharArray();
//your code goes here
}
}
i don't know how to go about it, all i have to do is reverse the string. uhg it was so easy in python with just the (::-) is that how its written idk it's been some time python.
anyways i would appreciate any help and advice on learning java effectively i don't know much yet, i tried going on leetcode but daaaaamn it was crazy hard, i didn't manage to do any problem. thank you