[알고리즘] 백준 - 2193 ( 이친수 ) / 자바

import java.util.Scanner;


public class Main {
	public static void main(String[] args) throws Exception {
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		if(N==0) {
			System.out.print(0);
			return;
		}
		long zero = 1;
		long one = 0;
		long temp = 0;
		for(int i = 1 ; i <N-1 ; i++) {
			temp = one;
			one = zero;
			zero = zero+temp;
		}
	
		System.out.print(one+zero);
		
	}
}