排序问题

list_a.sort() #改变list_a为有序状态
list_b = sorted( list_a ) #将list_a存为有序的list_b

#几种排序算法的实现
#选择排序法，每次遍历挑出最小值，O(n*n)
l_num=[1,34,4,63,4,7,47,2,48,654,4,57,32]
for i in range(len(l_num)-1):
    imin=i
    for j in range(i+1,len(l_num)):
        if l_num[j]<l_num[imin]:
            imin=j
    temp=l_num[i]
    l_num[i]=l_num[imin]
    l_num[imin]=temp
print(l_num)

#冒泡法，每次和相邻比较，O(n*n)
l_num=[1,34,4,63,4,7,47,2,48,654,4,57,32]
for i in range(len(l_num)):
    for j in range(len(l_num)-i-1):
        if l_num[j]>l_num[j+1]:
            temp=l_num[j]
            l_num[j]=l_num[j+1]
            l_num[j+1]=temp
print(l_num)

#插入排序，像打扑克的时候，每次输入都将它放在合适位置，O(n*n)
def Insertsort(b,a):
    if a==[]:
        a.append(b)
        return a
    for item in a:
        if item>b:
            i=a.index(item)
            c=a[i:]
            d=a[:i]
            d.append(b)
            a=d+c
            return a
    a.append(b)
    return a
l_num=[1,34,4,63,4,7,47,2,48,654,4,57,32]
ans=[]
for item in l_num:
    ans=Insertsort(item,ans)
print(ans)

#二分插入排序
def Insertsort2(b,a):
    left=0
    right=len(a)-1
    while(left<=right):
        mid=(left+right)//2
        if a[mid]>b:
            right=mid-1 
        else:
            left=mid+1
    a_l=a[:left]
    a_r=a[left:]
    a_l.append(b)
    return a_l+a_r
l_num=[1,34,4,63,4,7,47,2,48,654,4,57,32]
ans2=[]
for item in l_num:
    ans2=Insertsort2(item,ans2)
#    print(item," ",ans2)
print(ans2)

#还有快速排序，堆排序
#https://blog.csdn.net/u013178472/article/details/54926531