列表的排序和统计。

s1 = 'python,java,php,go,c,python,java,php,go,c,python,java,php,go,c,'
#统计每个单词出现的次数，
l1 = s1.split(',')
print(l1)
dic = {} #创建新字典
for i in l1 :
    if i not in dic:
        dic[i] = 1
    else:
        dic[i] = dic[i]+1  #存在就V加1
print(dic)
for k,v in dic.items():
    print(f'{k} : {v} 次')
import collections
collections.Counter(l1) #统计次数
for k,v in collections.Counter(l1).items():
    print(k,v,sep=' : ')

l1 = [1,2,3,4,2,4,2,6,8]
l2 = list()
# 列表排序
i = 0
for i in l1 :
    if i not in l2 :
        l2.append(i)
print(l2)
#count 统计次数
for i in l1:
    if i not in l2:  #
        l2.append(i)
        l2.append(str(1))
    else:
        l2[l2.index(i) + 1] = str(int(l2[l2.index(i) + 1])+1)
print(l2)
for i in range(0,len(l2),2):
    print(l2[i],l2[i+1],sep='----')