Python pythonLearing

Snakify

All answers of Snakify

Posted by Hsu on October 30, 2022

Snakify

SNAKIFY

CHAPTER 1

Sum of three numbers

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a = int(input())
b = int(input())
c = int(input())
print(a + b + c)

後記: input()出來是字串，要轉形

Hi John

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a=input()
print("Hi ",a)

後記: Python的print預設是間隔一空白(如果要改預設可用sep 或+ 處理)，並換行

Square

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2

a= int(input())
print(a*a)

Area of right-angled triangle

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b = int(input())
h = int(input())
print ( b*h/2 )

後記: Python這樣出來可以是float，不須管形別轉換，但C++要注意會不會強制轉換

Hello, Harry!

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name = input()
print("Hello",name,"!",sep='')

後記: 2行可改成 print('Hello, ' + input() + '!')

Apple sharing

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n = int(input())
K = int(input())
print(K//n)
print(K%n)

後記: //是整除

Previous and next

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a= int(input())
print("The next number for the number",a,"is",a+1)
print("The previous number for the number",a,"is",a-1)

Two timestamps

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a=int(input())
b=int(input())
c=int(input())
d=int(input())
e=int(input())
f=int(input())
print((d-a)*60*60+(e-b)*60+(f-c))

School desks

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import math
sum=0
for i in range(3):
    a=int(input())
    a=math.ceil(a/2) 
    sum=a+sum
print(sum)

CHAPTER 2

Last digit of integer

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2

a=int(input())
print(a%10)

Tens digit

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print(int(int(input())/10)%10)

Sum of digits

正常解法

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a= int(input())
frist=int(a/100)
second=int((a-frist*100)/10)
third=a%10
print(frist+second+third)

字串解

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a=input()
sum=0
for i in a:
    sum+=ord(i)-48
print(sum)

一行流

1

print(sum([ord(i)-48 for i in input()]))

後記: 可再延伸UVA題目: 10019 - Funny Encryption Method

Fractional part

理想的解法

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a=float(input())
b=int (a)
print(a-b)

實際解法

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a=input().split(".")
if (len(a)==2):
    print('0.'+a[1])
else:
    print(0)

後記: Float不精確，要用字串處理才能得到標準答案

First digit after decimal point

正常解法

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a=float(input())
b=float(int(a))
c=float((a-b)*10)
d=int(c)
print(d)

字串處理

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a=input()
if( a.find(".")==-1 ):
    print(0)
else:
    print(a[a.find(".")+1])

精簡化

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a=input()
print( (a[a.find(".")+1],0) [a.find(".")==-1] )

Car route

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N=int(input())
M=int(input())
Day=M//N
if (M%N>0):
    Day=Day+1
print(Day)

Snakify 解答

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import math
N=int(input())
M=int(input())
print(math.ceil(M/N))

Digital clock

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2

a=int(input())
print(a//60,a%60)

Total cost

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A=int(input())
B=int(input())
N=int(input())
dollar=(A*100+B)*N
print(dollar//100,dollar%100)

後記: Float不精確，改用int方式解

Clock face - 1

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H=int(input())
M=int(input())
S=int(input())
angle=float(H*30+M/2+S/120)
print(angle)

Clock face - 2

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degree=float(input())
print(degree*12%360)

後記: hour hand: min hand = 1 : 12

CHAPTER 3

Minimum of two numbers

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a=int(input())
b=int(input())
if (a>b):
    print(b)
else:
    print(a)

簡化

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a=int(input())
b=int(input())
print((a,b)[a>b])

Sign function

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a=int(input())
if(a>0):
    print(1)
elif (a<0):
    print(-1)
else:
    print(0)

Minimum of three numbers

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A=[0,0,0]
A[0]=int(input())
A[1]=int(input())
A[2]=int(input())
for i in range(2):
    if (A[i+1]>A[i]):
        tmp=A[i]
        A[i]=A[i+1]
        A[i+1]=tmp
print(A[2])

後記: Python 數值交換可以改成a,b=b,a，以元組形式

Equal numbers

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a=int(input())
b=int(input())
c=int(input())
if (a==b):
    if (b==c):
        print(3)
    else:
        print(2)
elif (b==c):
    if (a==b):
        print(3)
    else:
        print(2)
elif (c==a):
    if (a==b):
        print(3)
    else:
        print(2)
else:
    print(0)

Rook move

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A=[0,0,0,0]
for i in range(4):
    A[i]=int(input())
if (A[0]==A[2]):
    print("YES")
elif (A[1]==A[3]):
    print("YES")
else:
    print("NO")

Chess board - same color

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A=[0,0,0,0]
for i in range(4):
    A[i]=int(input())
if ((A[0]+A[1])%2 == (A[2]+A[3])%2):
    print("YES")
else:
    print("NO")

思路: 同顏色 $x+y$ 奇數(偶數)

King move

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A=[0,0,0,0]
for i in range(4):
    A[i]=int(input())
if (abs(A[0]-A[2])<=1 and abs(A[1]-A[3])<=1):
    print("YES")
else:
    print("NO")

後記: Python可以使用類似數學區間的表達式(-1<=A[0]-A[2]<=1)但C++不行，請注意

Bishop moves

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A=[0,0,0,0]
for i in range(4):
    A[i]=int(input())
if (abs(A[0]-A[2]) == abs(A[1]-A[3])):
    print("YES")
else:
    print("NO")

後記: abs()是取絕對值

Queen move

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A=[0,0,0,0]
for i in range(4):
    A[i]=int(input())
if (abs(A[0]-A[2]) == abs(A[1]-A[3])): #斜向移動
    print("YES")
elif (A[0]==A[2]):  #水平移動
    print("YES")
elif (A[1]==A[3]):  #鉛直移動
    print("YES")
else:
    print("NO")

Knight move

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A=[0,0,0,0]
for i in range(4):
    A[i]=int(input())
a=abs(A[0]-A[2])
b=abs(A[1]-A[3])
if (a==2 and b==1):
    print("YES")
elif (a==1 and b==2):
    print("YES")
else :
    print("NO")

Chocolate bar

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n=int(input())
m=int(input())
k=int(input())
if ((k%n==0 or k%m==0) and m*n>=k):
    print("YES")
else:
    print("NO")

後記: 這題多考慮兩種情況 1.長或寬可以整除所求 2.面積大於所求

Leap year

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year=int(input())
if (year%4==0 and year%100!=0):
    print("LEAP")
elif (year%400==0):
    print("LEAP")
else:
    print("COMMON")

CHAPTER 4

Series - 1

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a=int(input())
b=int(input())
for i in range (a,b+1):
    print(i)

Series - 2

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a=int(input())
b=int(input())
if (b>=a):
    for i in range(a,b+1):
        print (i)
elif (a>b):
    for i in range(a,b-1,-1):
        print(i)

Sum of ten numbers

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sum=0
for i in range(10):
    a=int(input())
    sum=sum+a
print(sum)

Sum of N numbers

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N=int(input())
sum=0
for i in range(N):
    a=int(input())
    sum=sum+a
print(sum)

Sum of cubes

正常作法

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N=int(input())
sum=0
for i in range(N+1):
    sum=sum+(i**3)
print(sum)

一行流

1

print(sum(map(lambda x:x**3,range(1,int(input())+1))))

思路: 用range()產生list並用map執行迭代，並回傳陣列給sum()並印出總和

Factorial

正常做法

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a=int(input())
b=a
mul=1
for i in range (b):
   mul=mul*a
   a=a-1
print(mul)

遞迴演算法

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f=lambda x: 1 if x==1 else x*f(x-1)
print( f(int(input())) )

The number of zeros

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sum=0
N=int(input())
for i in range(N):
   a=int(input())
   if (a==0):
       sum=sum+1
print(sum)

Adding factorials

正常作法

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N=int(input())
sum=0
for i in range(1,N+1,1):
    mul=1 
    for g in range (1,i+1,1):
        mul=mul*g
    sum=sum+mul
print(sum)

一層迴圈做法

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N=int(input())
sum=0
mul=1 
for i in range(1,N+1,1):
    mul=mul*i
    sum=sum+mul
print(sum)

遞迴演算法與Sum of Club應用

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f=lambda x: 1 if x==1 else x*f(x-1)
print(sum([f(int(i)) for i in range(1,int(input())+1)]))

Ladder

正常作法

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N=int(input())
for i in range(1,N+1,1):
    for g in range(1,i+1,1):
        print(g,end="")
    print()

一行流

1

for i in range(1,int(input())+1):print("".join([str(j) for j in range(1,i+1)]))

思路: 正常解法簡化即可 後記: join 只能用char,int不行

Lost card

標記解法

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N=int(input())
A=[i for i in range(1,N+1)]
for i in range(N-1):
    A.remove(int(input()))
print( A[0] )

特殊解

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N=int(input())
sum=0
for i in range (1,N):
    sum+=int(input())
print(int(N*(1+N)/2-sum))

CHAPTER 5

The number of words

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s=input()
print(s[2])
print(s[len(s)-2])
print(s[0:5])
print(s[0:len(s)-2])
print(s[0:len(s):2])
print(s[1:len(s):2])
print(s[-1:-(len(s)+1):-1])
print(s[-1:-(len(s)+1):-2])
print(len(s))

The number of words

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a=input().split(" ")
print(len(a))

The two halves

Slice

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a=input()
print(a[(len(a)+1)//2:]+a[:(len(a)+1)//2])

我的解法

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a=input()
a=list(a)
if (len(a)%2==0):
    for i in range(int(len(a)/2),len(a),1):
        print(a[i],end="")
    for i in range(0,int(len(a)/2),1):
        print(a[i],end="")
else:
    for i in range(int(len(a)/2)+1,len(a),1):
        print(a[i],end="")
    for i in range(0,int(len(a)/2)+1,1):
        print(a[i],end="")

To swap the two words

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s=input().split(" ")
for i in range(len(s)-1,-1,-1):
    print(s[i],end=" ")

The first and last occurrence

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s=input()
address=[]
for i in range(0,len(s),1):
    if (s[i]=='f'):
        address.append(i)
if (len(address)==1):
    print(address[0])
elif(len(address)==0):
    pass
else:
    print(address[0],address[len(address)-1])

The second occurrence

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s=input()
address=[]
for i in range(0,len(s),1):
    if (s[i]=='f'):
        address.append(i)
if (len(address)==1):
    print(-1)
elif(len(address)==0):
    print(-2)
else:
    print(address[1])

Remove the fragment

find()

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s=input()
print(s[ :s.find('h') ]+s[ s.rfind('h')+1: ] )

儲存成陣列

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s=input()
b=[]
for i in range(0,len(s),1):
    if (s[i]=='h'):
        b.append(i)

print(s[0:b[0]]+s[b[len(b)-1]+1: ])

Reverse the fragment

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s=input()
b=[]
for i in range(0,len(s),1):
    if (s[i]=='h'):
        b.append(i)

print(s[0:b[0]]+s[b[len(b)-1]-len(s):b[0]-len(s):-1]+s[b[len(b)-1]: ])

Replace the substring

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s=input()
for i in s:
    if (i=='1'):
        print("one",end="")
    else:
        print(i,end="")

Delete a character

Snakify 作法

1

print(input().replace('@',''))

我的解法

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s=input()
for i in s:
    if (i=='@'):
        pass
    else:
        print(i,end="")

Replace within the fragment

用find()

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s=input()
l,r=(s.find('h'),s.rfind('h'))
for i in range(len(s)):
    if (s[i]=='h'):
        if(i!=l and i!=r):
            print('H',sep='',end='')
        else:
            print('h',sep='',end='')
    else:
        print(s[i],sep='',end='')

用count()

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s=input()
count=0
h=s.count('h')
for i in s:
    if (i=='h'):
        if (count==0):
            count+=1
            print(i,end="")
            continue
        elif (count==h-1):
            count+=1
            print(i,end="")
            continue
        print("H",end="")
        count+=1
    else:
        print(i,end="")

思路: 第一個h和最後一個h不能改，可以用判斷第幾個h的方式執行，再者碰到第一個與最後一個h以continue的方式跳過

Delete every third character

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s=input()
for i in range(0,len(s),1):
    if (i%3==0):
        pass
    else:
        print(s[i],end="")

CHAPTER 6

:::success while迴圈

  1. 用在不確定次數的時候
  2. 裡面條件是TURE(1)會執行 :::

    List of squares

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a=int(input())
i=1
while (a>=i**2):
    print(i**2)
    i=i+1

Least divisor

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n=int(input())
i=2
while(n%i!=0):
    i=i+1
print(i)

The power of two

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n=int(input())
i=0
x=1
while (n>x):
    x=x*2
    i=i+1
    if(x*2>n):
        break
print(i,x)

Morning jog

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x=int(input())
y=int(input())
Day=1
while(x < y):
    x=x*1.1
    Day=Day+1
print(Day)

The length of the sequence

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i=0
a=int(input())
while(a!=0):
    a=int(input())
    i+=1
print(i)

The sum of the sequence

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a=int(input())
sum=0
while(a!=0):
    sum=a+sum
    a=int(input())
print(sum)

The average of the sequence

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count=0
a=int(input())
sum=0
while(a!=0):
    sum=sum+a
    a=int(input())
    count=count+1
print(sum/count)

The maximum of the sequence

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a=int(input())
max=a
while(a!=0):
    if(a>max):
        max=a
    a=int(input())
print(max)

The index of the maximum of a sequence

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address=1
max_address=1
a=int(input())
max=a
while(a!=0):
    if(a>max):
        max=a
        max_address=address
    a=int(input())
    address+=1
print(max_address)

後記: 類似於氣泡排序

The number of even elements of the sequence

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a=int(input())
count=0
while(a!=0):
    if (a%2==0):
        count+=1
    a=int(input())
print(count)

The number of elements that are greater than the previous one

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a=int(input())
tmp=a
count=0
while(a!=0):
    a=int(input())
    if (a>tmp):
        count+=1
    tmp=a
print(count)

The second maximum

Snakify解法(以兩變數實現)

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first_max = int(input())
second_max = int(input())
if first_max < second_max:
    first_max, second_max = second_max, first_max
element = int(input())
while element != 0:
    if element > first_max:
        second_max, first_max = first_max, element
    elif element > second_max:
        second_max = element
    element = int(input())
print(second_max)

本人解法(list實現)

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n=int(input())
b=[]
while(n!=0):
    b.append(n)
    n=int(input())
b.sort()
print(b[len(b)-2])

The number of elements equal to the maximum

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n=int(input())
b=[]
while(n!=0):
    b.append(n)
    n=int(input())
max_=max(b)
count=0
for i in b:
    if (max_==i):
        count+=1
print(count)

Fibonacci numbers

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n=int(input())
b=[0,1]
for i in range(1,n+1,1):
    b.append(b[i]+b[i-1])

print(b[len(b)-2])

The index of a Fibonacci number

Snakify作法(無unfind問題)

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a = int(input())
if a == 0:
    print(0)
else:
    fib_prev, fib_next = 0, 1
    n = 1
    while fib_next <= a:
        if fib_next == a:
            print(n)
            break
        fib_prev, fib_next = fib_next, fib_prev + fib_next
        n += 1
    else:
        print(-1)

本人作法(有unfind問題)

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b=[0,1]
for i in range(1,100,1):
    b.append(b[i]+b[i-1])
f=int(input())
flag=0
for i in range(0,100,1):
    if (b[i]==f):
        print(i)
        flag=1
        break
if (flag==0):
    print(-1)

後記: 看完解答才想到可以用兩變數(fib1,fib2)的方式實現，既不會浪費太多記憶體也不會浪費太多時間

The maximum number of consecutive equal elements

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n=int(input())
pre=0
count=1
max_count=1
while n!=0:
    if n==pre:
        count+=1
        max_count=max(max_count,count)
    else:
        count=1
    pre=n
    n=int(input())
print(max_count)

思路: 用count的方式跟最大數到的數字比，若比較大則取代之

CHPTER 7

:::success List 1.單行輸入用列表生成式實現[ int(i) for i in input().split()] 2.多行輸入用append實現 3.切片技巧很方便 :::

Even indices

正常解

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a=input().split(" ")
for i in range(0,len(a),2):
    print(a[i],end=" ")

一行流

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print(" ".join([i for i in input().split(' ')][0::2]))

Even elements

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a=[ int(i) for i in input().split()]
for i in a:
    if (i%2==0):
        print( i , end=' ')

後記: 列表生成式很好用 [ int(i) for i in input().split()] 可以直接生成一個列表

Greater than previous

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a=[int(e) for e in input().split()]
i=0
for _ in a:
    if (i >= 1):
            if (a[i]>a[i-1]):
                print(a[i] ,end=" ")
    i=i+1

Neighbors of the same sign

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a = [int(i) for i in input().split()]
for i in range(1,len(a),1):
    if (a[i]*a[i-1]>0):
        print(a[i-1],a[i],sep=" ",end=" ")
        break

Greater than neighbours

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a = [int(i) for i in input().split()]
flag=0
for i in range(1,len(a)-1,1):
    if (a[i]>a[i-1] and a[i]>a[i+1]):
        flag+=1
print(flag)

The largest element

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a = [int(g) for g in input().split()]
max_ = a[0]
address = 0
for i in range(1,len(a),1):
    if (a[i]>max_):
        address = i
        max_ = a[i]

print(max_ , address)

The number of distinct elements

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a=[i for i in input().split()]
count=0
for i in range (1,len(a),1):
    if (a[i]!=a[i-1]):
        count+=1
print(count+1)

Swap neighbours

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a=[i for i in input().split()]
for i in range(0,len(a),2):
    if (len(a)%2!=0):
        if (i==len(a)-1):
            break
        tmp=a[i+1]
        a[i+1]=a[i]
        a[i]=tmp
    
    else:
        tmp=a[i+1]
        a[i+1]=a[i]
        a[i]=tmp
for i in range(0,len(a),1):
    print(a[i],end=' ')

Swap min and max

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a=[int(e) for e in input().split()]
b=a.index(max(a))
c=a.index(min(a))
a[b],a[c]=a[c],a[b]


for i in a:
    print(i,end=" ")

The number of pairs of equal

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a=[int(i) for i in input().split()]
count=0
for i in range (0,len(a),1):
    for j in range(i+1,len(a),1):
        if (a[i]==a[j]):
            count+=1
print(count)

Unique elements

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a=[int(i) for i in input().split()]
flag=0
for i in range(0,len(a),1):
    for j in range(0,len(a),1):
        if (i != j):
            if (a[i]==a[j]):
                flag=1
    if (flag==0):
        print(a[i],end=" ")
    flag=0

Queens

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a=[]
for i in range(8):
    row_list=[int(g) for g in input().split()]
    a.append(row_list)
flag=0
for i in range(8):
    for g in range(8):
        if(i==g):
            break
        elif ((abs(a[i][0]-a[g][0]))==(abs(a[i][1]-a[g][1]))):
            flag=1
        elif (a[i][0]==a[g][0]):
            flag=1
        elif (a[i][1]==a[g][1]):
            flag=1
if (flag==1):
    print("YES")
else:
    print("NO")

後記: 個人認為本章最困難的一題，有偷偷用二維陣列實現，但也是可以用一維處理

The bowling alley

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N,K=map(int,input().split())
a=[]
for i in range(K):
    row_array=[int(g) for g in input().split()]
    a.append(row_array)
    
pin=[1]*N
for i in range(K):
    for j in range(a[i][0]-1,a[i][1],1):
        pin[j]=0
for i in range(N):
    if (pin[i]==0):
        print(".",sep="",end="")
    elif (pin[i]==1):
        print("I",sep="",end="")

後記: 用bool的想法似乎又再多浪費時間，直接用.和I還比較快

CHAPTER 8

The length of the segment

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import math

def distance(a,b):
    dis=math.sqrt(a**2+b**2)
    return dis

x1=float(input())
y1=float(input())
x2=float(input())
y2=float(input())
print(distance(abs(x2-x1),abs(y2-y1)))

Negative exponent

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def power(a,b):
    return a**b
print(power(float(input()),float(input())))

Uppercase

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def capitalize(a):
    return chr(ord(a)-32)
a=input()
for i in range(0,len(a),1):
    if(a[i-1]==' '):
        print(capitalize(a[i]),end="")
    elif (i==0):
        print(capitalize(a[i]),end="")
    else:
        print(a[i],end="")

後記: ASCII表大寫小寫差32(小寫比較大)

:::warning 以下開始是遞迴 :::

Exponentiation

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def f(x,y):
    if(y==1):
        return x
    elif (y==0):
        return 1
    else:
        return f(x,y-1)*x
x=float(input())
y=float(input())
print(f(x,y))

Reverse the sequence

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def f():
    a=int(input())
    if (a!=0):
        f()
    # Isn't 0 it will keep input
    print(a)
    # when a=0 it will print
f()

Fibonacci numbers

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def fib(n):
    if (n==1):
        return 1
    elif (n==0):
        return 0
    return fib(n-1)+fib(n-2)
n=int(input())
print(fib(n))

CHAPTER 9

Maximum

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#Initialized & Input
a=[]
row,col=map(int,input().split())
for i in range(row):
    c=[int(i) for i in input().split()]
    a.append(c)
    
#Processing
max_=a[0][0]
address_x,address_y=0,0
for i in range(row):
    for j in range(col):
        if (a[i][j]>max_):
            max_=a[i][j]
            address_x,address_y=i,j
            
#Print
print(address_x,address_y)

Snowflake

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#Initialized & Input
N=int(input())
a=[['.']*N for i in range(N)]

#Processing the list
for i in range(N):
    for j in range(N):
        if ( i==(N-1)/2 or j==(N-1)/2 ):
            a[i][j] = "*"
        elif (i == j):
            a[i][j] = "*"
        elif (i+j==(N-1)):
            a[i][j] = "*"
            
#Print
for i in range(N):
    for j in range(N):
            print(a[i][j],end=" ",sep=" ")
    print()

Chess board

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#Initialized & Input
row,col=[int(i) for i in input().split()]
a=[["."]*col for i in range(row)]

#Processing the list
for i in range(row):
    for j in range(col):
        if (i%2==1):
            if (j%2==0):
                a[i][j] = "*"
        elif (i%2==0):
            if (j%2==1):
                a[i][j] = "*"
                
#Print
for i in range(row):
    for j in range(col):
        print(a[i][j],end=" ",sep=" ")
    print()

注意: line 3 [["."]*col for i in range(row)] 不能寫成[["."]*col]*row此種寫法的指標會和row=0時相同(原因是Python =和C++ = 概念不同)

The diagonal parallel to the main

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n = int(input())
for i in range(n):
    for j in range(-i,n-i,1):
        print (abs(j),end=" ",sep=" ")
    print()

Side diagonal

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n=int(input())
a=[[0]*n for i in range(n)]
for i in range(n):
    for j in range(n):
        if (i+j==n-1):
            a[i][j]=1
        elif (i+j>n-1):
            a[i][j]=2
for i in range(n):
    for j in range(n):
        print(a[i][j],sep=" ",end=" ")
    print()

Swap the columns

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row,col=map(int,input().split())
a=[]
for i in range(row):
    a.append([int(j) for j in input().split()])
change1,change2=map(int,input().split())
for i in range(row):
    tmp=a[i][change2]
    a[i][change2]=a[i][change1]
    a[i][change1]=tmp
for i in range(row):
    for j in range(col):
        print(a[i][j],sep=" ",end=" ")
    print()

Scale a matrix

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row,col=map(int,input().split())
a=[]
for i in range(row):
    a.append([int(i) for i in input().split()])
product=int(input())
for i in range(row):
    for j in range(col):
        a[i][j]=a[i][j]*product
        print(a[i][j],end=" ",sep=" ")
    print()

Multiply two matrices

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m,n,r=map(int,input().split())
A=[]
B=[]
for i in range(m):
    A.append([int(j) for j in input().split()])
for i in range(n):
    B.append([int(j) for j in input().split()])
C=[[0]*r for i in range(m)]
for j in range(m):
    for g in range(r):
        for i in range(n):
            C[j][g]=C[j][g]+A[j][i]*B[i][g]
for i in range(m):
    for g in range(r):
        print(C[i][g],end=" ")
    print()

CHAPTER 10

The number of distinct numbers

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A={int(i) for i in input().split()}
max_=max(A)
count=0
for i in range(max_+1):
    if (i in A):
        count+=1
print(count)

The number of equal numbers

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print(len(set(input().split()).intersection(set(input().split()))))

The intersection of sets

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print(" ".join(sorted(set(input().split()).intersection(set(input().split())))))

Has the number been encountered before

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A=[int(i) for i in input().split()]
for i in range(len(A)):
    if A[i] in A[0:i]:
        print("YES")
    else:
        print("NO")

Cubes

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M,N=map(int,input().split())
Alice=set()
Bod=set()
for i in range(M):
    Alice.add(input())
for i in range(N):
    Bod.add(input())
print(len(Alice&Bod))
print("\n".join(sorted(Alice&Bod)))
print(len(Alice-Bod))
print("\n".join(sorted(Alice-Bod,key=lambda x:int(x))))
print(len(Bod-Alice))
print("\n".join(sorted(Bod-Alice)))

The number of distinct words in some text

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n=int(input())
sets=set()
for i in range(n):
    line=input().split()
    for j in line:
        if j not in sets:
            sets.add(j)
print(len(sets))

Guess the number

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all_={int(i) for i in range(1,int(input()))}
possible=all_
while True:
    guess=input()
    if guess=="HELP":
        break
    guess={int(i) for i in guess.split()}
    ans=input()
    if ans=="YES":
        possible &= guess
    elif ans=="NO":
        possible &= (all_-guess)
print(" ".join([str(i) for i in possible]))

Polyglots

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n=int(input())
language=[]
for i in range(int(input())):
    language.append(input())
general=set(language)
all_=set(language)
for i in range(n-1):
    language=[]
    for j in range(int(input())):
        language.append(input())
    general&=set(language)
    all_|=set(language)

general=sorted(list(general),key= lambda x:ord(x[0]))
all_=sorted(list(all_),key = lambda x:ord(x[0]))
print(len(general))
for i in general:
    print(i)
print(len(all_))
for i in all_:
    print(i)

CHAPTER 11

Number of occurrences

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a=input().split()
dic=dict()
for i in a:
    if i not in dic:
        print(0,end=" ")
        dic[i]=1
    
    else:
        print(dic[i],end=" ")
        dic[i]+=1

Dictionary of synonyms

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n=int(input())
dic=dict()
for i in range(n):
    a=[j for j in input().split()]
    dic[a[0]]=a[1]

word=input()
if word in dic:
    print(dic[word])
else:
    new_dic={v:k for k,v in dic.items()}
    print(new_dic[word])

Elections in the USA

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n=int(input())
dic={}
for i in range(n):
    a=[i for i in input().split()]
    a[1]=int(a[1])
    if a[0] not in dic:
        dic[a[0]]=a[1]
    elif a[0] in dic:
        dic[a[0]]+=a[1]
new_dic=sorted(dic.items(),key= lambda x:(ord(x[0][0])))
for k,v in new_dic:
    print(k,v)

The most frequent word

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n=int(input())
dic=dict()
for i in range(n):
    a=input().split()
    for j in a:
        if j not in dic:
            dic[j]=1
        else:
            dic[j]+=1
new=sorted(dic.items(),key= lambda x:(x[1],-ord(x[0][0])),reverse=True)
print(new[0][0])

Access rights

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n=int(input())
access={}
for i in range(n):
    program=input().split()
    access[program[0]]=program[1:len(program)]

m=int(input())
for i in range(m):
    program=input().split()
    if "W" in access[program[1]] and program[0]=="write":
        print("OK")
    elif "R" in access[program[1]] and program[0]=="read":
        print("OK")
    elif "X" in access[program[1]] and program[0]=="execute":
        print("OK")
    else:
        print("Access denied")

Countries and cities

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n=int(input())
dic={}
for i in range(n):
    cities=input().split()
    for city in cities[1:]:
        dic[city]=cities[0]

m=int(input())
for i in range(m):
    location=input()
    print(dic[location])

Frequency analysis

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n=int(input())
dic={}
for i in range(n):
    line=input().split()
    for j in line:
        if j not in dic:
            dic[j]=1
        else:
            dic[j]+=1
new=[(-j,i) for (i,j) in dic.items()]
new=sorted(new)
for i,j in new:
    print(j)

English-Latin dictionary

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dic={}
for i in range(int(input())):
    line=input().split(" - ")
    latin=line[1].split(", ")
    for i in latin:
        if i in dic:
            dic[i].append(line[0])
        else:
            dic[i]=[line[0]]
print(len(dic))
for i in sorted(dic):
    print(i,"-",", ".join(dic[i]))
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