题解 | #斐波那契数列#递推思路

    public int Fibonacci(int n) {
        if(n == 1){
            return 1;
        }
        if(n == 2){
            return 1;
        }
        int a = 1;
        int b = 1;
        int res = 0;
        for(int i = 3;i<=n;i++){
            res = a + b;
            a = b;
            b = res;
        }
        return res;
    }
}