内排序之直接选择排序

直接选择排序的套路比较容易理解，就是从待排的元素里，挑最小或最大的出来，放到前面，然后迭代指针往后移一位...
直接上代码：

def select_sorting(ary):
    n = len(ary)
    for i in range(n):
        min_index = i
        for j in range(i + 1, n):
            if ary[j] < ary[min_index]:
                min_index = j
        ary[i], ary[min_index] = ary[min_index], ary[i]
    return ary

if __name__ == "__main__":
    arr1 = [3, 1, 2, 0, 4, -2]
    print arr1
    print(select_sorting(arr1))