斐波那契序列

你可以使用遞迴計算 Fibonacci 序列中的數字。

遵循 F(n)= F（n-2）+ F（n-1）的數學理論，對於任何 i> 0，

// Returns the i'th Fibonacci number
public int fib(int i) {
    if(i <= 2) {
        // Base case of the recursive function.
        // i is either 1 or 2, whose associated Fibonacci sequence numbers are 1 and 1.
        return 1;
    }
    // Recursive case. Return the sum of the two previous Fibonacci numbers.
    // This works because the definition of the Fibonacci sequence specifies
    // that the sum of two adjacent elements equals the next element.
    return  fib(i - 2) + fib(i - 1);
    
}

fib(10); // Returns 55