I'm fairly new to programming. I'm trying to repeat the word in a given string the amount of times by a given number in the same string. I have decided to loop through the string and add each char to a new string to print out but I'm getting an out of index error.
final String string = "Hello";
final int num = 3;
int number = string.length() * num;
String str = "";
for (int i = 0; i < number; i++) {
str += string.charAt(i);
}
System.out.println(str);
You are getting the error because the value of i is going beyond the last index available in Hello. The last index in Hello is "Hello".length() - 1 whereas the value of i is going beyond this value because of your loop terminating condition:
i < string.length() * num;
By the way, if you want to repeat Hello 3 times, you should do it as
for(int i = 0; i < num; i ++){
System.out.print(string);
}
Demo:
public class Main {
public static void main(String[] args) {
final String string = "Hello";
final int num = 3;
for (int i = 0; i < num; i++) {
System.out.print(string);
}
}
}
String#repeatWith Java 11+, you can do it without using a loop by using String#repeat:
System.out.println(string.repeat(num));
Demo:
public class Main {
public static void main(String[] args) {
final String string = "Hello";
final int num = 3;
System.out.println(string.repeat(num));
}
}
Just keep it simple
String string = "Hello";
int num = 3;
for (int i = 0; i < num; i++) {
System.out.println(string);
}
If you want to have your result in a new String you can just do this :
String string = "Hello";
int num = 3;
String res = "";
for (int i = 0; i < num; i++) {
res += string;
}
System.out.println(res);
Just adding this in here since you stated you're learning. Java has a StringBuilder class, super easy to use
And according this this induvial class using StringBuilder is incredibly more efficient than concatenate.
chartype in Java is obsolete. Unable to handle even half the characters defined in Unicode. Learn to use Unicode code point integer numbers instead.