Python Exercise analysis

1. Print less than 10 even: bit operation

for i in range(10):        if not i & 0x01:                print(i)

2. Given a positive integer that does not exceed 5 bits, it is judged by several (using the input function)

Method One: normal logical processing

a = int(input("Please enter a numer: "))if a < 0:        print(‘Error‘)if a < 10:        print(1)elif a < 100:        print(2)elif a < 1000:        print(3)elif a < 10000:        print(4)elif a < 100000:        print(5)else:        print(‘Error‘)

Method Two: Binary

val=input("Please enter a numer: ")val=int(val)if val>=1000:        if val>=10000:                print("这是五位数")        else:                print("这是四位数")else:        if val>=100:                print("这是三位数")        elif val>=10:                print("这是两位数")        else:                print("这是一位数")

Method Three: String processing

a = str(int(input("Please enter a number: ")))print(len(a))

3. Given a positive integer no more than 5 bits, determine the number of digits, then print out the digits of bits, 10, hundred, Thousand, million

Method One:

val=input(‘>>>‘)      val=int(val)print(val)if val>=1000:        if val>=10000:                num=5        else:                 num=4else:                   if val>=100:                num=3        elif val>=10:                num=2        else:                 num=1print(num)pre=0for i in range(num,0,-1):        cur=val//(10**(i-1))        print(cur-pre*10)        pre=cur

Method Two:

num =int(input("请输入一个数字："))print(num)countnum=0while True:        print(num%10)        num=num//10        countnum+=1        if num==0:                break

Print ("The number of digits you entered is:", Countnum)
Method Three:

c=int(input(">>>"))w=10000x=lengthflag =Falsewhile w:        t=c//w        if flag:                print(t)        else:                if t:                        print(t)                        flag=True                else:                        x -= 1        c %= w        w//=10print("这个数的位数是",x)

4. Print a square with a side length of n

Method One:

a = int(input("Please enter a number: "))for i in range(a):        if i == 0 or i == a-1:                print(‘*‘ * a )        else:                print(‘*‘ + ‘ ‘ * (a - 2) + ‘*‘)

Method Two:

a = int(input("Please enter a number: "))print(‘*‘ * a)for i in range(a - 2):        print(‘*‘ + ‘ ‘ * (a - 2) + ‘*‘)else:print(‘*‘ * a)

Method Three:

a = int(input("Please enter a number: "))top = mid = ‘*‘for i in range(a - 1):        top += ‘\t*‘        mid += ‘\t‘else:        mid += ‘*‘        print(top)for i in range(a - 2):        print(‘\n‘)        print(mid)else:        print(‘\n‘)        print(top)

5. Ask for all odd and (2500) in 100

sum = 0for i in range(1,100,2):        sum += iprint(sum)    

6. Judge student achievement, Grade a~e. Among them, 90 points above is ' A ', 80~89 divides into ' B ', 70~79 divides into ' C ', 60~69 divides into ' D ', 60 points below is ' E '

a = int(input(‘Please enter a score: ‘))if a > 79:        if a >= 90:                print(‘A‘)        else:                print(‘B‘)elif a >= 70:        print(‘C‘)elif 60 <= a < 69:        print(‘D‘)else:        print(‘E‘)

7. Ask for 1 to 5 the sum of factorial

Method One:

sum = 0for i in range(1,6):        mul = 1        for j in range(1,i + 1):                mul *= j        sum += mulprint(sum)

Method Two: High efficiency

sum = 0mul = 1for i in range(1,6):        mul *= i        sum += mulprint(sum)

8. Find the area and perimeter of the circle

r=int(input(">>>"))print("area="+str(3.14*r*r))print("circumference="+str(2*3.14*r))

9. Enter a number of numbers, print out the maximum value, if the input is empty, exit the program
m = Int (input (">>>"))
While True:
c = input (">>>")
If C:
n = Int (c)
If n > M:
m = n
Print ("Max is", m)
Else
Break

10. Enter the number of N to calculate the arithmetic average for each input.

count = 0sum = 0while True:    num = int(input(">>>"))    count += 1    sum += num    print("avg is ",sum / count)    if num == 0:            break

11. Give a number to determine whether it is prime (prime)

a=int(input("Please enter a number: "))for i in range(2,int(a ** 0.5) + 1):        if a % i != 0:                continue        elif a % i == 0:                print(("N: %d") % (i))                break        else:        print("Yes,prime")

12. Print 99 multiplication table

Method One:

for i in range(1,10):        line = ‘‘        for j in range(1,i + 1):                line = line + (‘%d*%d=%2d ‘) % (j,i,i*j)        print(line)

Method Two: List analytic type

[print("{}*{}={:<3}".format(j,i,i*j),end=‘\n‘ if i ==j else ‘‘) for i in range(1,10) for j in range(1,i+1)]

13. Print Diamond

Method One:

for i in range(-3,4):        if i<0:                prespace=-i        else:                prespace=i        print(‘ ‘*prespace + ‘*‘*(7-prespace*2))

Method Two:

n =int(input(">>>"))e = n//2for i in range(-e,e+1):        if i < 0 :                p = -i        else:                p =i        print(" "*p+ "*"*(n-2*p))

14. Print Lightning Graphics
Method One:

for i in range(-3,4):        if i<0:                print(‘ ‘*(-i) + ‘*‘*(4+i))        elif i>0:                print(‘ ‘*3 + ‘*‘*(4-i))        else:                print(‘*‘*7)

Method Two:

n =int(input(">>>"))e = n//2for i in range(-e,e+1):        if i < 0 :                print(" "*(-i)+‘*‘*((e+1)+i))        elif i > 0:                print(" "*e + ‘*‘*((e+1)-i))        else:                print("*"*n)

15. Print to the top triangle
Method One:

for i in range(-3,4):        x = -i if i < 0 else i        print(" "*(3-x)+"*"*(2*x+1))

Method Two:

n =int(input(">>>"))e = n//2for i in range(-e,e+1):        x = -i if i < 0 else i        print(" "*(e-x)+"*"*(2*x+1))

16. Print the Fibonacci sequence within 100

a=0b=1print(1)while True:        c=a+b        if c>100:                break        a=b        b=c        print(c)

17.101th of the Fibonacci sequence 573147844013817084101
Method One:
A = 0
b = 1
Print (0,a)
Print (1,B)
index = 2
While True:
c = A + b
Print (INDEX,C)
If index = = 101:
Break
A = b
B = C
Index + = 1

Method Two:

a = 0b = 1for _ in range(100):        a, b = b , a+bprint(b)

18. Ask for all primes within 100,000 9592

Method One: (Simplify first)

for x in range(2,100):        for i in range(2,x):                if x%i==0:                        break        else:                print(x,end=" ")

Method Two:

for x in range(3,10000,2):        for i in range(3,int(x**0.5)+1):                if x%i==0:                        break        else:                print(x,end=" ")

Method Three:

import timestart= time.clock()number = 100000count = 2for num in range(4,number):        if num%6 != 1 and num%6 != 5:                continue        else:                snum = int(num**0.5+1)                for i in range(5,snum):                        if not num%i:                                break                else:                        count += 1print(count)end=time.clock()print("run:{}".format(end-start))

Method Four: (the use of prime characteristics: more than 3 of prime forms are 6n-1 and 6n+1)

import timestart= time.clock()number = 100000count = 2for num in range(4,number):        if num%6 != 1 and num%6 != 5:                continue        else:                snum = int(num**0.5+1)                for i in range(5,snum):                        if not num%i:                                break                else:                        count += 1print(count)end=time.clock()print("run:{}".format(end-start))

19. Reverse Multiplication Table:

Method One:

for i in range(1,10):        line = ‘‘        for j in range(i,10):                        line += ‘%d*%d=%2d ‘ % (i,j,j * i)        print(‘ ‘ * (7 * i - 6) + line)

Method Two:

for i in range(1,10):        line = ‘‘        for j in range(i,10):                        line += ‘%d*%d=%2d ‘ % (i,j,j * i)        print(‘{:>63}‘.format(line))

Method Three:

for i in range(1,10):        line = ‘‘        for j in range(i,10):                        line += ‘{}*{}={:<{}} ‘.format(i,j,j * i,2 if j<4 else 3)        print(‘{:>70}‘.format(line))

20. Monkeys Eat Peach:

n=1for i in range(1,10):        n=(n+1)*2print(n)

Python Exercise analysis