def merge(a, b):
    i, j = 0, 0;
    ans = []
    for k in range(len(a) + len(b)):
        if(i != len(a) or j != len(b)):
            if(a[i] >= b[j]):
                ans.append(b[j])
                j =+ 1
            else:
                ans.append(a[i])
                i =+ 1
        elif(i == len(a)):
            ans.append(b[j])
            j += 1
        elif(j == len(b)):
            ans.append(a[i])
            i += 1
        else:
            return ans
    return ans

def mergesort(a):
    if(len(a) == 1):
        return 1
    b = mergesort(a[:len(a)/2])
    c = mergesort(a[len(a)/2:])
    return merge(b, c)

wow = [1923, 312, 4, 21, 432 ,432, 0, -100, 1, -1999, 27, 4848, 9]
print(mergesort(wow))