1
def search(key,a):    #如果查找失败返回-1，否则，返回所在位置。
2
    for i in range(len(a)):
3
        if a[i] == key:
4
            return i
5
    return -1
6
def main():
7
    a = [12,21,24,28,30,42,77,80,94,98]
8
    k = int(input("请输入:"))
9
    pos = search(k,a)
10
    if pos == -1:
11
        print("不存在!")
12
    else:
13
        print("下标为:",pos)
14
main()

1
def binarySearch(key,a):
2
    low = 0
3
    high = len(a)-1
4
    while low <= high:
5
        mid = (low+high)//2
6
        if key > a[mid]:
7
            low = mid+1
8
        elif key < a[mid]:
9
            high = mid - 1
10
        else:
11
            return mid
12
    return -1
13
def main():
14
    a = [12,21,24,28,30,42,77,80,94,98]
15
    k = int(input("请输入:"))
16
    pos = binarySearch(k,a)
17
    if pos == -1:
18
        print("不存在!")
19
    else:
20
        print("下标为:",pos)
21
main()

1
def BubbleSort(num):      # (从小到大)
2
    n = len(num)
3
    for i in range(0, n-1):
4
        for j in range(0, n-i-1):   #从0到n-2.
5
            if num[j+1] <= num[j]:
6
                num[j], num[j+1] = num[j+1], num[j]
7
    return num
8

9
def main():
10
    a = [24,12,28,80,30,42,77,94,21,98]#输入
11
    BubbleSort(a)
12
    print(a)
13
main()

1
def selection_sort(arr):
2
    n = len(arr)-1
3
    for i in range(n):
4
        min_idx = i
5
        for j in range(i+1, n):
6
            if arr[j] < arr[min_idx]:
7
                min_idx = j
8
        arr[i], arr[min_idx] = arr[min_idx], arr[i]
9
        print(arr)
10
a = [2, 3, 5, 6, 1, -1, 7, 9]
11
selection_sort(a)