Were given an array of n numbers a1 n and want to add up

Question

Question :

We're given an array of n numbers, A[1 · · · n] and want to add up the n numbers.

Let's consider the following divide-and-conquer algorithm: It partitions the array into two subarrays, A[1 · · · n/2] and A[n/2 + 1 · · · n] and recurse on them to compute A[1] + · · · + A[n/2], and A[n/2 + 1] + · · · + A[n]. Then it adds up the two sums and return the value.

What is the recurrence for the running time? Solve it.