Method mergeSort

Sorting/Homework/mergeSort.cpp:37–55

    }
    
    vector<int> mergeSort(vector<int>& nums,int start, int end) {
        //Base Case
        if (start>end){
            return {};
        }
        if (start==end){
            return {nums[start]};
        }
        
        //Calculate Mid
        int mid= start+(end-start)/2;
            
        //MergeSortCall
        vector<int> A = mergeSort(nums,start,mid);
        vector<int> B = mergeSort(nums,mid+1,end);
        
        //MergeCall
        return merge(A,B);
    }
    
    vector<int> sortArray(vector<int>& nums) {
        int n=nums.size();