In Merge Sort, what is the maximum number of comparisons required to merge two already-sorted subarrays of sizes 4 and 3 into a single sorted array of size 7?

When merging two sorted subarrays of sizes m and n, the merge procedure compares elements from the front of each subarray one at a time, moving the smaller one into the output array, until one subarray is fully exhausted (at which point the remainder of the other subarray is simply copied over without further comparisons). In the worst case, this requires m + n − 1 comparisons (one fewer than the total number of elements, since the very last remaining element never needs a comparison — it's simply appended). For m=4 and n=3: comparisons = 4 + 3 − 1 = 6.