Final answer:
Merge sort is an efficient sorting algorithm with a time complexity of O(n log n) and a space complexity of O(n). It works by dividing the array into halves, sorting each half, and then merging the sorted halves back together.
Step-by-step explanation:
Merge sort is an efficient sorting algorithm that falls under the category of divide and conquer. It works by dividing the array into equal halves, sorting each half recursively, and then merging the sorted halves back together. One of the most correct statements about the complexity of merge sort is that it has a time complexity of O(n log n), where n is the number of elements in the array.
This means that as the size of the array increases, the time taken to sort the array grows at a rate proportional to n multiplied by the logarithm of n. This makes merge sort a highly efficient algorithm for large datasets.
Another correct statement is that merge sort has a space complexity of O(n), meaning that it requires additional memory space to store the temporary arrays used during the merging step. However, this space requirement is still considered efficient in most cases.