list deduplication method

list deduplication

Method 1: The cyclic deduplication

s= [1,1,2,2,2,3,4,4]
res= []
for i in s:
    if i not in res:
        res.append(i)

print(res)

s1= list(set(s))
print(s1)

 

　　Method 2: use the dictionary to heavy

res_d ={}
for i in s:
    if i in res_d:
        res_d[i] += 1
    else:
        res_d[i] =1

print(res_d)

for k,v in res_d.items():
    print(k)

Method 3: set to heavy, reconverted list

print(list(set(s)))

Method 4: erasing index

s = [1,1,1,2,2,3,4,4]
t= s[1:]
for i in s:
    while t.count(i) > 1:
        del t[t.index(i)]

print(t)

Method 5: Using reduce, lambda functions to weight

from functools import reduce
l1 = [1,1,1,2,2,3,4,4,4]
func = lambda x,y:x if y in x else x+[y]
print(reduce(func,[[],]+l1))