Practice tracing this recursive algorithm. The first few lines are provided below. Suggestion: write out the function calls in a nested format with spaces. /** Sorts the elements in a range of an array. @param a the array with the elements to sort @param from start of the range to sort @param to end of the range to sort Use example array[7] = {13,9,3,15,6,19,1}, At call from main(), from = 0, to = 6 */ void merge_sort(int a[], int from, int to) { if (from == to) { return; } int mid = (from + to) / 2; // Sort the first half and the second half merge_sorta(a, from, mid); merge_sortb(a, mid + 1, to); merge(a, from, mid, to); }

Trace:

from main() ... merge_sort (a, 0, 6)

merge_sort_a (a, 0, 3)

merge_sort_a (a, 0, 1)