插入排序优化

def selection_sort(alist):
    n = len(alist)
    # 需要进行n-1次选择操作
    a = 0
    for i in range(n-1):
        # 记录最小位置
        min_index = i
        exit = i
        # 从i+1位置到末尾选择出最小数据
        for j in range(i+1, n):
            a +=1
            # print('这是第%d次循环'%a)
            if alist[j-1] <= alist[j]:
                exit += 1

            if exit + 1 == len(alist):
                print('结束112')
                return

            if alist[j] < alist[min_index]:
                min_index = j
        # 如果选择出的数据不在正确位置，进行交换
        if min_index != i:
            alist[i], alist[min_index] = alist[min_index], alist[i]
        
        print('这是第%d轮结束%s'%(i,alist))
    print('这是第%d轮结束%s>>'%(i,alist))

# alist = [54,226,93,17,77,31,44,55,20]
alist = [1,2,2,5,7,6]
selection_sort(alist)
print(alist)