1.打印10以内偶数：位运算
for i in range(10):
if not i & 0x01:
print(i)2.给定一个不超过5位的正整数，判断其有几位（使用input函数）
方法一：正常逻辑处理
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')方法二：折半
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")方法三：字符串处理
a = str(int(input("Please enter a number: ")))
print(len(a))3.给定一个不超过5位的正整数，判断该数的位数，依次打印出个位、十位、百位、千位、万位的数字
方法一：
val=input('>>>')
val=int(val)
print(val)
if val>=1000:
if val>=10000:
num=5
else:
num=4
else:
if val>=100:
num=3
elif val>=10:
num=2
else:
num=1
print(num)
pre=0
for i in range(num,0,-1):
cur=val//(10**(i-1))
print(cur-pre*10)
pre=cur方法二：
num =int(input("请输入一个数字："))
print(num)
countnum=0
while True:
print(num%10)
num=num//10
countnum+=1
if num==0:
breakprint("您输入的位数是：",countnum)
方法三：
c=int(input(">>>"))
w=10000
x=length
flag =False
while w:
t=c//w
if flag:
print(t)
else:
if t:
print(t)
flag=True
else:
x -= 1
c %= w
w//=10
print("这个数的位数是",x)4.打印一个边长为n的正方形
方法一：
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) + '*')方法二：
a = int(input("Please enter a number: "))
print('*' * a)
for i in range(a - 2):
print('*' + ' ' * (a - 2) + '*')
else:
print('*' * a)方法三：
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.求100内所有奇数的和（2500）
sum = 0
for i in range(1,100,2):
sum += i
print(sum) 6.判断学生成绩，成绩等级A~E。其中，90分以上为'A'，80~89分为'B'，70~79分为'C'，60~69分为'D'，60分以下为'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.求1到5阶乘之和
方法一：
sum = 0
for i in range(1,6):
mul = 1
for j in range(1,i + 1):
mul *= j
sum += mul
print(sum)方法二：效率高
sum = 0
mul = 1
for i in range(1,6):
mul *= i
sum += mul
print(sum)8.求圆的面积和周长
r=int(input(">>>"))
print("area="+str(3.14*r*r))
print("circumference="+str(2*3.14*r))9.输入若干个数，打印出最大值，如果输入为空，退出程序
m = int(input(">>>"))
while True:
c = input(">>>")
if c:
n = int(c)
if n > m :
m = n
print("max is",m)
else:
break
10.输入n 个数 求每次输入的算术平均数。
count = 0
sum = 0
while True:
num = int(input(">>>"))
count += 1
sum += num
print("avg is ",sum / count)
if num == 0:
break11.给一个数，判断它是否是素数（质数）
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.打印九九乘法表
方法一：
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)方法二：列表解析式
[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.打印菱形
方法一：
for i in range(-3,4):
if i<0:
prespace=-i
else:
prespace=i
print(' '*prespace + '*'*(7-prespace*2))方法二：
n =int(input(">>>"))
e = n//2
for i in range(-e,e+1):
if i < 0 :
p = -i
else:
p =i
print(" "*p+ "*"*(n-2*p))14.打印闪电图形
方法一：
for i in range(-3,4):
if i<0:
print(' '*(-i) + '*'*(4+i))
elif i>0:
print(' '*3 + '*'*(4-i))
else:
print('*'*7)方法二：
n =int(input(">>>"))
e = n//2
for 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.打印对顶三角形
方法一：
for i in range(-3,4):
x = -i if i < 0 else i
print(" "*(3-x)+"*"*(2*x+1))方法二：
n =int(input(">>>"))
e = n//2
for i in range(-e,e+1):
x = -i if i < 0 else i
print(" "*(e-x)+"*"*(2*x+1))16.打印100以内的斐波那契数列
a=0
b=1
print(1)
while True:
c=a+b
if c>100:
break
a=b
b=c
print(c)17.求斐波那契数列第101项 573147844013817084101
方法一：
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
方法二：
a = 0
b = 1
for _ in range(100):
a, b = b , a+b
print(b)18.求10万内的所有素数 9592
方法一：（先简单化）
for x in range(2,100):
for i in range(2,x):
if x%i==0:
break
else:
print(x,end=" ")方法二：
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=" ")方法三：
import time
start= time.clock()
number = 100000
count = 2
for 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 += 1
print(count)
end=time.clock()
print("run:{}".format(end-start))方法四：（利用素数特性：大于3的素数形式都是6N-1和6N+1）
import time
start= time.clock()
number = 100000
count = 2
for 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 += 1
print(count)
end=time.clock()
print("run:{}".format(end-start))19.反向乘法表：
方法一：
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)方法二：
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))方法三：
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.猴子吃桃：
n=1
for i in range(1,10):
n=(n+1)*2
print(n)