피보나치

public class Main {
    public static void main(String[] args) {
		// 공식
        //An = An-1 + An-2; n>=3
        //처음 값을준다
        int []arr = new int[100];

        arr[1] = 1;
        arr[2] = 1;

        for (int i =3;i<100;i++){
            arr[i] = arr[i-1]+arr[i-2];
        }

        for (int i=1; i<10;i++){
            System.out.println(arr[i] + "");
        }
        
          //2번쨰 방법.
        //An
        //An = An-1 + An-2; n>=3
        int prevPrevNum = 1; //An-2
        int preNum = 1;      //An-1

        System.out.println(prevPrevNum+"111");
        System.out.println(preNum+"2222222");

        for (int i=3; i<10;i++){
            int nNum = prevPrevNum+preNum;
            System.out.println(nNum+"333");
            preNum =nNum;
            prevPrevNum = preNum;

        }
    }
}

결과 값
1
1
2
3
5
8
13
21
34