例如:[70, 88, 91, 70, 107, 234, 91, 177, 282, 197]
--- 去重之后 [70, 88, 91, 107, 234, 177, 282, 197]
---- 降序排序 [282, 234, 197, 177, 107, 91, 88, 70]
nums=[70, 88, 91, 70, 107, 234, 91, 177, 282, 197]
nums1=[]
for i in nums:
if i not in nums1:
nums1.append(i)
print(f'去重后:{nums1}')
print(f'降序排序后:{sorted(nums1,reverse=True)}')
去重后:[70, 88, 91, 107, 234, 177, 282, 197]
降序排序后:[282, 234, 197, 177, 107, 91, 88, 70]
a. 生成一个存放1-100中各位数为3的数据列表
结果为 [3, 13, 23, 33, 43, 53, 63, 73, 83, 93]
print([i for i in range(3,100,10)])
b. 利用列表推到是将 列表中的整数提取出来
例如:[True, 17, "hello", "bye", 98, 34, 21] --- [17, 98, 34, 21]
nums=[True, 17, "hello", "bye", 98, 34, 21]
print([i for i in nums if type(i)==int])
c.利用列表推导式 存放指定列表中字符串的长度
例如: ["good", "nice", "see you", "bye"] --- [4, 4, 7, 3]
print([len(i) for i in nums ])
d. 利用列表推导式删除列表中整数个位数小于5的元素
例如:[24, 'abc', 99, True, 21, 38, 'hello'] --- ['abc', 99, True, 38, 'hello']
nums=[24, 'abc', 99, True, 21, 38, 'hello']
print([i for i in nums if not(type(i)==int and i%10<5)])
e. 利用列表推导式获取元素是元组的列表中每个元组的最后一个元素
例如:[(10, 20, 30), ('abc', 'hello'), (1, 2, 3.4), (True, False)] --- [30, 'hello', 3.4, False]
print([i[len(i)-1] for i in nums])
f.利用列表推导式将数字列表中所有的奇数乘以2,所有的偶数除以2
例如: [23, 4, 67, 88, 90, 21] -> [46, 2, 134, 44, 45, 42]
nums=[23, 4, 67, 88, 90, 21]
print([i*2 if i%2==1 else i//2 for i in nums])
已知一个列表获取列表中指定元素所有的下标
例如:[10, 20, 34, 10, 9, 78]
10的下标:[0, 3]
20的下标:[1]
30的下标:[]
nums=[10, 20, 34, 10, 9, 78]
list1=[]
for i in nums:
if i not in list1:
list1.append(i)
print(list1)
for i in list1:
list2=[]
for j in range(len(nums)):
if i ==nums[j]:
list2.append(j)
print(f'{i}的下标:{list2}')
10的下标:[0, 3]
20的下标:[1]
34的下标:[2]
9的下标:[4]
78的下标:[5]
data =[10, 20, 34, 10, 9, 78]
for j in set(data):
list1 = []
for i, x in enumerate(data):
if x==j:
list1.append(i)
print(f'{j}的下标{list1}')
*已知一个数字列表,写程序判断这个列表时候是连续递增列表。
例如:
[1, 2, 3, 4, 5] -> True
[23, 45, 78, 90] -> True
[1, 3, 2, 4, 5] -> False
nums=[23, 45, 46, 90]
for i in range(1,len(nums)):
if nums[i]<=nums[i-1]:
print(False)
break
else:
print(True)
已知两个列表,将两个列表按照下面的规律交叉合并
A = [10, 20, 30, 40, 50]
B = [100, 200, 300]
结果:[10, 100, 20, 200, 30, 300, 40, 50]
A = [10, 20, 30, 40, 50]
B = [100, 200, 300]
if len(A)<len(B):
A,B=B,A
for i in range(len(B)):
A.insert(1+2*i,B[i])
print(A)
[10, 100, 20, 200, 30, 300, 40, 50]
已知两个有序列表,将两个列表合并,合并后的新列表中元素仍然是递增列表
A = [10, 20, 30, 40, 50]
B = [25, 44, 60]
结果:[10, 20, 25, 30, 40, 45, 50, 60]
A = [10, 20, 30, 40, 50]
B = [25, 44, 60]
print(sorted(A+B))
[10, 20, 25, 30, 40, 44, 50, 60]
A = [10, 20, 30, 40, 50]
B = [25, 44, 60,10,5,40]
for j in B:
for i in range(len(A)-1):
if A[i]<=j<=A[i+1]:
A.insert(i+1,j)
break
elif j<=A[0]:
A.insert(0,j)
break
elif j >=A[len(A)-1]:
A.append(j)
break
print(A)
[5, 10, 10, 20, 25, 30, 40, 40, 44, 50, 60]