归并排序 @ Python

归并排序 @ Python

def merge_sort(A):
    length = len(A)
    if length <= 1:
        return A 
    else:
        result = []
        left = merge_sort(A[:length / 2])
        right = merge_sort(A[length / 2:])
        i = 0
        j = 0
        l_length = len(left)
        r_length = len(right)
        # 合并的过程
        while i < r_length and j < l_length:
            if left[0] <= right[0]:
                result.append(left[0])
                left.pop(0)
                i += 1
            else:
                result.append((right[0]))
                right.pop(0)
                j += 1

        return result + left + right


print merge_sort([98, 111, 23, 12, 3434, 1211, 1, 21])