如何复制最后的X位？

string = "Hello, World!"
x = 5
result = string[-x:]
print(result)

World!

String string = "Hello, World!";
int x = 5;
String result = string.substring(string.length() - x);
System.out.println(result);

World!

let string = "Hello, World!";
let x = 5;
let result = string.slice(-x);
console.log(result);

World!