Please answer the following question using C++

Write a program that implements two functions as follows: (a) A function called fibonacci ( ) , which would compute the first 21 Fibonacci numbers Fo, F1,.. F20- The formal arguments of the function should be the array storing the Fibonacci numbers, and the size of the array. The first two Fibonacci num- bers are Fo - 0, F1 - 1, and thereafter each successive Fibonacci number Fi is the sum of the two preceding Fibonacci numbers Fi-1 and Fi-2 (b) A function called gcd (...), which takes as input arguments the array of Fibonacci numbers, computed earlier, and two integer indices in the array, each greater than 0 The function should return the ged of the two elements of the array, indicated by the indices