(Solved): In c++ please 11.12 LAB: Fibonacci sequence (recursion) The Fibonacci sequence begins with 0 and the ...

11.12 LAB: Fibonacci sequence (recursion) The Fibonacci sequence begins with 0 and then 1 follows. All subsequent values are the sum of the previous two, for example: 0, 1, 1, 2, 3, $5,8,13$. Complete the Fibonacci() function, which takes in an index, $n$, and returns the nth value in the sequence. Any negative index values should return -1 . Ex: If the input is: 7 the output is: Fibonacci(7) is 13 Note: Use recursion and DO NOT use any loops.