归并排序

def solve():
    def merge_sort(____):
        if len(____) <= ____:
            return lst
        mid = len(____) // ____
        left = merge_sort(____)
        right = merge_sort(____)
        return merge(____)
    def merge(____):
        result = []
        i = j = ____
        while i < len(____) and j < len(____):
            if l[i] <= r[j]:
                result.append(____)
                i += ____
            else:
                result.append(____)
                j += ____
        result.extend(____)
        result.extend(____)
        return result
    print(merge_sort(____))