Tuple

Tuple vs. List

ใช้ tuple เหมาะกว่า

ใช้ tuple เพื่อปกป้องการแก้ไข

แบบฝึกหัด: Polynomial

Set

Set Methods

A = {1,2,3,4,5}
B = {3,4,5,6,7}
C = A.union(B)        # {1,2,3,4,5,6,7}
C = A | B             # {1,2,3,4,5,6,7}
C = A.intersection(B) # {3,4,5}
C = A & B             # {3,4,5}
C = A.difference(B)   # {1,2}
C = A - B             # {1,2}
C.add(9)              # {1,2,9}
C.remove(1)           # {2,9}
print( A <= B, A.issubset(B) ) # True True
for e in A:
    print(e)
C = A ^ B

การสร้างเซตจากข้อมูลในที่เก็บต่าง ๆ

s = set( [1,2,3,1] )
s = set( (1,2,3,1) )
s = set( "Mono" )
s = set( {"A":2, "B":2} )
s = set( {1,2,3} )
s = set( range(1,7,2) )

➔
➔
➔
➔
➔
➔

s = {1,2,3}
s = {1,2,3}
s = {"M", "o", "n"}
s = {"A", "B"}
s = {1,2,3}
s = {1,3,5}

การสร้างลิสต์จากข้อมูลในที่เก็บต่าง ๆ

x = list( [1,2,3,1] )
x = list( (1,2,3,1) )
x = list( "Mono" )
x = list( {"A":2, "B":2} )
x = list( {1,2,3} )
x = list( range(1,7,2) )

➔
➔
➔
➔
➔
➔

x = [1,2,3,1]
x = [1,2,3,1]
x = ["M", "o", "n", "o"]
x = ["A", "B"]
x = [1,2,3]
x = [1,3,5]

การสร้างทูเปิลจากข้อมูลในที่เก็บต่าง ๆ

t = tuple( [1,2,3,1] )
t = tuple( (1,2,3,1) )
t = tuple( "Mono" )
t = tuple( {"A":2, "B":2} )
t = tuple( {1,2,3} )
t = tuple( range(1,7,2) )

➔
➔
➔
➔
➔
➔

t = (1,2,3,1)
t = (1,2,3,1)
t = ("M", "o", "n", "o")
t = ("A", "B")
t = (1,2,3)
t = (1,3,5)

sort vs. sorted

def sorted(x) :
    out = []
    for e in x:
        out.append(e)
    out.sort()
    return out

x = sorted( [1,4,3,2] )
x = sorted( {1,4,3,2} )
x = sorted( "hello" )
x = sorted( {22:2, 90:3, 3:23} )

➔
➔
➔
➔

x = [1, 2, 3, 4]
x = [1, 2, 3, 4]
x = ["e", "h", "l", "l", "o"]
x = [3, 22, 90]

for   elem   in   a_set

55555
11111
66666
22222
33333
44444

if  e  in  set  ทำงานเร็วกว่า   if  e  in   list

import time
def search_all(X):
    b = time.time()
    n = len(X)
    for i in range(n):
        if i in X:     # True
            pass
    for i in range(n):
        if (n+1) in X: # False
            pass
    print(time.time() - b)

n = 50000
L = []
for i in range(n):
    L.append(i)
S = set()
for i in range(n):
    S.add(i)

search_all(L)
search_all(S)

41.84556722640991
0.0149579048156738

ตัวอย่าง: ฟังก์ชันตรวจข้อมูลซ้ำกันในลิสต์

def has_duplicate( x ):
    for i in range(len(x)-1):
        for j in range(i+1, len(x)):
            if x[i] == x[j]:
                return True
    return False

def has_duplicate( x ):
    d = sorted(x)
    for i in range(len(x)-1):
        if d[i] == d[i+1]:
            return True
    return False

ตัวอย่าง: ฟังก์ชันตรวจข้อมูลซ้ำกันในลิสต์

def has_duplicate( x ):
    s = set( x )
    return len(s) != len(x)

def has_duplicate( x ):
    s = set()
    for e in x:
        if e in s:
            return True
        s.add(e)
    return False

ตัวอย่าง: หาสองจำนวนต่างกันที่รวมกันได้ k

x = [int(e) for e in input().split()]
d = set(x)
k = int(input())
soln = []
for e in d:
    e1 = k - e
    if e < e1 and e1 in d:
        soln.append((e, e1))
if len(soln)==0:
    print("Not found")
else:
    print(soln)

ตัวอย่าง: Sieve of Eratosthenes

10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
20, 21, 22, 23, 24, 25, 26, 27, 28, 29,
30, 31, 32, 33, 34, 35, 36, 37, 38, 39,
40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50 }

S1 = set(range(2, N+1))
for i in range(2, int(N**0.5) + 1):
    S2 = set(range(2*i, N+1, i))
    S1 = S1 - S2

{ 4,  6,  8, 10, ..., 50}
{ 6,  9, 12, 15, ..., 48}
{ 8, 12, 16, 20, ..., 48}
{10, 15, 20, 25, ..., 50}
{12, 18, 24, 30, ..., 48}
{14, 21, 28, 35, ..., 49}

แบบฝึกหัด: Winner

5
Chelsea Liverpool
ManU Liverpool
Liverpool ManU
Chelsea Arsenal
Everton ManCity

List  vs.  Dict

x = [ "6130102321", "6130238221", "6031022121" ]
p = [ [10, 9, 10],  [9, 10, 8],   [5, 8, 7]    ]

x = [ [6130102321, [10,  9, 10]],
      [6130238221, [ 9, 10,  8]],
      [6031022121, [ 5,  8,  7]] ]

d = { "6130102321": [10,  9, 10],
      "6130238221": [ 9, 10,  8],
      "6031022121": [ 5,  8,  7]  }

List  vs.  Dict

x = [ "6130102321","6130238221","6031022121" ]
p = [ [10, 9, 10], [9, 10, 8],  [5, 8, 7]    ]

ID = input()
if ID in x:
    print( p[x.index(ID)] )

t = []
for i in range(len(x)):
    t.append([x[i],p[i]])
t.sort()
for id, sc in t:
    print(id, sc)

List  vs.  Dict

x = [ [6130102321, [10,  9, 10]],
      [6130238221, [ 9, 10,  8]],
      [6031022121, [ 5,  8,  7]] ]

List  vs.  Dict

d = { "6130102321": [10,  9, 10],
      "6130238221": [ 9, 10,  8],
      "6031022121": [ 5,  8,  7]  }

ID = input()
if ID in d:
    print( d[ID] )

แบบฝึกหัด: เรียงประเภทเพลงตามเวลารวม

9
Shake It Off, Taylor Swift, Pop, 3:39
Rolling In The Deep, Adele, Pop, 3:48
Chandelier, Sia, Pop, 3:36
Roar, Katy Perry, Pop, 3:42
Hotel California, Eagle, Rock, 6:30
We Are the Champions, Queen, Rock, 2:59
Hello Dolly, Louis Armstrong, Jazz, 2:27
Bohemian Rhapsody, Queen, Rock, 5:55
Coward of the County, Kenny Rogers, Country, 4:20

Rock --> 15:24
Pop --> 14:45
Country --> 4:20

More on Dict

ตัวอย่าง: dict

birthdate = {
      "6130192221": (31,12,2000),
      "6131022521": (28,2,2000),
      "6230012121": (3,4,2001)
    }

ID = input().strip()
print("Birth date of", ID, "is", birthdate[ID])
print("Birth year of", ID, "is", birthdate[ID][2])

series = {
      "Ranee": {"Roy Marn", "Plerng Boon"},
      "Urassaya": {"Maya Tawan","Kleun Cheewit"}
    } 

name = input().strip()
print(name, "starred in", ", ".join( series[name] ))

ตัวอย่าง: ตัวการ์ตูน

Ted, bear
Pongo, dog
Fozzie, bear
Winnie-the-Pooh, bear
Nana, dog
Scooby Doo, dog
Garfield, cat
Yogi, bear
Tom, cat
Sylvester, cat
Figaro, cat
Pluto, dog
Baloo, bear
Goofy, dog
Felix, cat
q

ตัวอย่าง: ตัวการ์ตูน

cartoon = {}
x = input()
while x != 'q':
    name, atype = x.split(", ")
    if atype not in cartoon:
        cartoon[atype] = {name}
    else:
        cartoon[atype].add(name)
    x = input()
print(cartoon)

แบบฝึกหัด: แสดงข้อมูลการ์ตูน ตามลำดับที่อ่านเข้ามา

Ted, bear
Pongo, dog
Fozzie, bear
Winnie-the-Pooh, bear
Nana, dog
Hello Kitty, cat
Scooby Doo, dog
Garfield, cat
Yogi, bear
Tom, cat
Sylvester, cat
Pluto, dog
Goofy, dog
q

bear: Ted, Fozzie, Winnie-the-Pooh, Yogi
dog: Pongo, Nana, Scooby Doo, Pluto, Goofy
cat: Hello Kitty, Garfield, Tom, Sylvester

More on Dict: keys(), values(), items()

D = { "Vios": "Toyota", "Fortuner": "Toyota",
      "Wave": "Honda", "Civic": "Honda" }

for k in D.keys():
    print(k)

for v in D.values()
    print(v)

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

Civic
Fortuner
Vios
Wave
Honda
Toyota
Toyota
Honda
Civic Honda
Fortuner
Toyota
Vios Toyota
Wave Honda

ตัวอย่าง: reverse mapping

r = { }
for k,v in d.items():
    r[v] = k
return r

if v not in r:
    r[v] = {k}
else:
    r[v].add(k)

r = { }
for k,v in d.items():
    if v not in r:
        r[v] = set()
    r[v].add(k)
return r

แบบฝึกหัด: ใครร้องเพลงนี้

11
Hello, Adele
Shake It Off, Taylor Swift
Chandelier, Sia
You've got a Friend, Carol King
Hello, Lionel Richie
What a Wonderful World, Anne Murray
Hello, Prince
What a Wonderful World, Louis Armstrong
You've got a Friend, James Taylor
What a Wonderful World, Rod Stewart
Hello, Sai Wa Si Bor Tim Gun, You've got a Friend

Hello -> Adele, Lionel Richie, Prince
Sai Wa Si Bor Tim Gun -> Not found
You've got a Friend -> Carol King, James Taylor

สรุป string, list, tuple, set, dict