相关简单算法代码（顺序，二分，冒泡，插入，选择等）

顺序查找

def linear_search(li,val):
    for i,k in enumerate(li):
        if k == val:
            return i

    else: # for循环完毕后一定会执行else
        return None

二分法查找

# 二分算法代码

def  binary_search(list,val):
    left = 0
    right = len(list)-1
    while left<=right:  # 候选区有值
        mid = (left + right) // 2
        if list[mid] ==val:
            return mid
        elif list[mid] > val:
            right = mid - 1
        else:
            left = mid + 1
    else:
        return  None
list = [1,2,3,4,4,6,7]
print(binary_search(list,8))

冒泡排序

#　冒泡排序
def bubble_sort(li):
    for i in range(len(li)-1): # i表示趟数
        exchange = False       # 没有移动数字
        for j in range(len(li)-i-1):
            if li[j] > li[j+1]:
                li[j],li[j+1] = li[j+1],li[j]
                exchange = True
        print(li)
        if not exchange:
            break



li = [1,2,3,4,6,5,8]
f = bubble_sort(li)

插入排序

# 插入排序
def insert_sort(li):
    for i in range (1,len(li)): # i表示拿到的数字索引
        j = i-1 # j 表示有序区最后一个的索引
        tmp = li[i]
        while j>=0 and li[j]>tmp:
            li[j+1] = li[j]
            j -= 1
        li[j+1] = tmp
        print(li)


li = [1,5,6,8,5,2]
print(li)
insert_sort(li)

选择排序

# 选择排序
def select_sort(li):
    for i in range (len(li)-1): # i 表示趟数
        for j in range(i+1,len(li)):
            if li[j]<li[i]: #li[i]表示最小
                li[i],li[j] = li[j],li[i]
        print(li)


li = [2,1,2,5,6]
print(li)
select_sort(li)