How do you reverse a string in Ruby?

How do you reverse a string in Ruby?

reverse is a String class method in Ruby which is used to return a new string with the characters from the given string in reverse order.

1. Syntax: str.reverse.
2. Parameters: Here, str is the string which is to be reversed.
3. Returns: This method returns a new string in reversed order.

How do you get the first 3 characters of a string in Ruby?

Getting the first n characters To access the first n characters of a string in ruby, we can use the square brackets syntax [] by passing the start index and length. In the example above, we have passed the [0, 3] to it. so it starts the extraction at index position 0 , and extracts before the position 3 .

How do you reverse the string with preserving the position of spaces?

Mark the space position of the given string in this string. Insert the character from the input string into the result string in reverse order. While inserting the character check if the result string already contains a space at index ‘j’ or not. If it contains, we copy the character to the next position.

Which method is used to show reverse of a string?

2. Reverse a String using String Builder / String Buffer Class. StringBuffer and StringBuilder comprise of an inbuilt method reverse() which is used to reverse the characters in the StringBuffer.

How do you reverse an array in Ruby?

Array#reverse() : reverse() is a Array class method which returns a new array containing self’s elements in reverse order.

1. Syntax: Array.reverse()
2. Parameter: Array.
3. Return: a new array containing self’s elements in reverse order.

How do you remove the first character of a string in Ruby?

To remove the first character of a string in Ruby, we can use the built-in slice!() method by passing a character index. Here is an example, that removes the first character w from the following string.

How can a string be reversed without affecting memory size?

You can’t change it, as it is immutable. What you want is to create a new string, and for this you need new memory. Strings are immutable–the contents of a string object cannot be changed after the object is created, although the syntax makes it appear as if you can do this.

How do you reverse a word in a string in Java?

Java Program to reverse each word in String

1. public class StringFormatter {
2. public static String reverseWord(String str){
3. String words[]=str.split(“\\s”);
4. String reverseWord=””;
5. for(String w:words){
6. StringBuilder sb=new StringBuilder(w);
7. sb.reverse();
8. reverseWord+=sb.toString()+” “;

How do you reverse a number?

How to reverse a number mathematically.

1. Step 1 — Isolate the last digit in number. lastDigit = number \% 10.
2. Step 2 — Append lastDigit to reverse. reverse = (reverse * 10) + lastDigit.
3. Step 3-Remove last digit from number. number = number / 10.
4. Iterate this process. while (number > 0)

How do you reverse a StringBuilder?

Example 1

1. public class StringBuilderReverseExample1 {
2. public static void main(String[] args) {
3. StringBuilder sb = new StringBuilder(“programming”);
4. System.out.println(“string = ” + sb);
5. // reversing of stringbuilder.
6. System.out.println(“reverse = ” + sb.reverse());
7. }
8. }

reverse is a String class method in Ruby which is used to return a new string with the characters from the given string in reverse order. Parameters: Here, str is the string which is to be reversed. Returns: This method returns a new string in reversed order.

How to return last line result in a method in Ruby?

In ruby you don’t have to return a value explicitly. Last line result in a method will be returned by default. In this case, the return value of ‘puts’ method is nil. So the return value of method ‘cat’ is nil. If you are looking for a return string, you can just put a string at the last line of the method ‘cat’ as @Arup suggested.

Does Ruby swap every byte from the beginning to the end?

“This swaps every byte from the beginning with every byte from the end until both indexes meet at the center” – pre-1.9.2 that would be true, as Ruby considered characters to be equivalent to bytes. In 1.9+ they could be multiple bytes but still be a single character. – the Tin Man

How to get the return string of a method?

If you are looking for a return string, you can just put a string at the last line of the method ‘cat’ as @Arup suggested. That will work. Share Improve this answer