백준 2748번: 피보나치 수 2

문제 출처: https://www.acmicpc.net/problem/2748

import java.io.BufferedReader;
import java.io.InputStreamReader;
 
public class Main {
    public static void main(String[] args) throws Exception {
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
        int n = Integer.parseInt(reader.readLine());
        long a = 0, b = 1, result = 0;
 
        if(n == 1){
            result = 1;
        }
        else {
            for(int i=2 ; i<=n ; i++){
                result = a + b;
                a = b;
                b = result;
            }
        }
 
        System.out.println(result);
    }
}