对于许多复杂问题，基本问题之一是经常遇到在python列表中找到大于某个数字的数字。
# find number of elements > k using for loop
# initializing list
test_list = [1, 7, 5, 6, 3, 8]
# initializing k
k = 4
# printing list
print ("The list : " + str(test_list))
# using for loop to get numbers > k
count = 0
for i in test_list :
if i > k :
count = count + 1
# printing the intersection
print ("The numbers greater than 4 : " + str(count))
# find number of elements > k using list comprehension
# initializing list
test_list = [1, 7, 5, 6, 3, 8]
# initializing k
k = 4
# printing list
print ("The list : " + str(test_list))
# using list comprehension to get numbers > k
count = len([i for i in test_list if i > k])
# printing the intersection
print ("The numbers greater than 4 : " + str(count))
# find number of elements > k using sum()# initializing list
test_list = [1, 7, 5, 6, 3, 8]
# initializing k
k = 4
# printing list
print ("The list : " + str(test_list))
# using sum() to get numbers > k
count = sum(i > k for i in test_list)
# printing the intersection
print ("The numbers greater than 4 : " + str(count))输出结果
The list : [1, 7, 5, 6, 3, 8] The numbers greater than 4 : 4 The list : [1, 7, 5, 6, 3, 8] The numbers greater than 4 : 4 The list : [1, 7, 5, 6, 3, 8] The numbers greater than 4 : 4