how to reverse a string

1# in order to make a string reversed in python 
2# you have to use the slicing as following
3
4string = "racecar"
5print(string[::-1])
6

1'String'[::-1] #-> 'gnirtS'

1'hello world'[::-1]
2'dlrow olleh'

1function reverseString(str) {
2    return str.split("").reverse().join("");
3}
4reverseString("hello");

1#linear
2
3def reverse(s): 
4  str = "" 
5  for i in s: 
6    str = i + str
7  return str
8
9#splicing
10'hello world'[::-1]

1String str = "Hello";
2String reverse(String str){
3  StringBuilder sb = new StringBuilder();
4  sb.append(str);
5  sb.reverse();
6  return sb.toString();
7}