Read the question, write Java on the right, then Run or Check.
QuestionHint and solution stay closed until you open them
Read n; print 1+2+…+n.
Examples
Input
5
Output
15
Input
1
Output
1
Hint
- n * (n + 1) / 2 works too.
Show correct code
Peek only after you have tried. You can still Check your own version.
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
int n = in.nextInt();
System.out.println(n * (n + 1) / 2);
}
}
Main.javaJava 21 · javac · Ctrl + Enter runs
ResultIdle
Run to see output. Check grades the tests.