Java bootcamp · Lab 14

Fibonacci n

mediumWhile12 minLesson: While

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QuestionHint and solution stay closed until you open them

Read n (1-indexed). Print the n-th Fibonacci number (F1=1, F2=1).

Examples

Example 1
Input
1
Output
1
Example 2
Input
6
Output
8
Hint
  1. Keep two running values a,b.
Show correct code

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import java.util.Scanner;

public class Main {
  public static void main(String[] args) {
    Scanner in = new Scanner(System.in);
    int n = in.nextInt();
    long a = 1, b = 1;
    for (int i = 3; i <= n; i++) { long c = a + b; a = b; b = c; }
    System.out.println(n == 0 ? 0 : b);
  }
}
Main.javaJava 21 · javac · Ctrl + Enter runs
ResultIdle
Run to see output. Check grades the tests.