In C++

Problem 4: (4 points) 4-way Merge Sort Consider a variation of Merge sort called 4-way Merge sort. Instead of splitting the array into two parts like Merge sort, 4-way Merge sort splits the array into four parts. 4-way Merge divides the input array into fourths, calls itself for each fourth and then merges the four sorted fourths. Implement 4-way Merge sort from Problem 4 to sort an array/vector of integers and name it merge4. Implement the algorithm in the same language you used for the sorting algorithms in HW 1. Your program should be able to read inputs from a file called "data.txt" where the first value of each line is the number of integers that need to be sorted, followed by the integers (like in HW 1). The output will be written to a file called "merge4.txt" a)