Question

我需要在不使用内置sort（）的情况下对此列表进行排序。我想我可以使用插入排序，但我以前从未真正使用它。我的代码似乎没有用。这有什么问题？谢谢。

fruits = ['grape', 'banana', 'strawberry', 'apple', 'peach', 'cherry']



for i in range(1, len(fruits)):
    tmp = fruits[i]
    j = i-1;
    while (j>0 and fruits[j] > tmp):
        fruits[j+1] = fruits[j]
        j = j-1
        fruits[j+1] = tmp
print(fruits)

Answer 1

我改变了两件事并且有效。不完全是一个答案，但可能会帮助你前进。

fruits = ['grape', 'banana', 'strawberry', 'apple', 'peach', 'cherry']

for i in range(0, len(fruits)):
    tmp = fruits[i]
    j = i-1;
    print(fruits)
    while (j>-1 and fruits[j] > tmp):
        fruits[j+1] = fruits[j] 
        j = j-1
        fruits[j+1] = tmp

print(fruits)

可以通过这种方式变小：

fruits = ['grape', 'banana', 'strawberry', 'apple', 'peach', 'cherry']

for i in range(len(fruits)):

    tmp = fruits[i]
    j = i-1 # stop index
    while (j > -1 and fruits[j] > tmp):
        fruits[j:j+2] = tmp,fruits[j] #swap places
        j -= 1

print(fruits)

返回：

['apple', 'banana', 'cherry', 'grape', 'peach', 'strawberry']

Answer 2

内循环中出现的交换操作似乎很奇怪。如果我是一个投注者，我会说这是错误发生的地方。

尝试做一个干净的“交换”，就像你为三个变量做的那样：

a = 10
b = 20
tmp = a
a = b
b = tmp
print(a) # prints 20
print(b) # prints 10

您的代码将变为：

for i in range(1, len(fruits)):
    j = i-1
    while j >= 0 and fruits[j] > fruits[j+1]:
        # Swap the two consecutive elements which are unsorted
        tmp = fruits[j]
        fruits[j] = fruits[j+1]
        fruits[j+1] = tmp
        # Prepare to process previous two consecutive elements
        j = j-1

Answer 3

首先用len（）替换镜头（）。

另一方面，你没有在fruits数组上应用你的函数，你只声明函数。

最后，数组从索引0开始，因此j必须是＆gt; = 0。

更正后的代码：

fruits = ['grape', 'banana', 'strawberry', 'apple', 'peach', 'cherry']

def insertion_sort(fruits):

   for i in range(1, len(fruits)):
       tmp = fruits[i]
       j = i-1;
       while (j>=0 and fruits[j] > tmp):
           fruits[j+1] = fruits[j];
           j = j-1;
      fruits[j+1] = tmp;
   return fruits

if __name__ == "__main__":

     fruits2 = insertion_sort(fruits)
     print(fruits2)

Answer 4

fruits = ['grape', 'banana', 'strawberry', 'apple', 'peach', 'cherry']
for i in range(1,len(fruits))
temp=fruits[i]
k = i
    while k > 0 and tmp < fruits[k - 1]:
        fruits[k] = fruits[k - 1]
        k -= 1
    fruits[k] = tmp
print fruits

你的循环将执行少一次 J = I-1 J＆大于0 它应该是 J＆-1个

Answer 5

这也完美！

Fruits= ['grape', 'banana', 'strawberry', 'apple', 'peach', 'cherry']
def insertionSortFruits():
    for i in range(1,len(Fruits)):
        key=Fruits[i]
        j=i-1
        while j>=0 and key<Fruits[j]:
            Fruits[j+1]=Fruits[j]
            j=j-1
        Fruits[j+1]=key
    print(Fruits)

#Testing
insertionSortFruits()

python，插入排序，字符串

5 个答案: