prime 探討

import math
def is_prime(n):
    if n<=1:
        return False
    for i in range(2,int(math.sqrt(n))+1):
        if n%i==0:
            return False
    return True

for i in range(100):
    if is_prime(i):
        print(i)

位數轉換

n=19
bians=""
while n>0:
    r=str(n%2)
    bians=r+bians
    n=n//2
print(bians)

======建立函數 =====

def conver(n,base):
    result=" "
    while n>0:
        r=n%base
        result=str(r)+result
        n=n//base
    return result

print(conver(4,2))

找零計算

import sys
yougive=input("你投多少錢")
if not yougive.isdecimal():
    print("要數字")
    sys.exit()
price=input("物品價值")

if not price.isdecimal():
    print("要數字")
    sys.exit()
change=int(yougive)-int(price)

if change < 0:
    print("錢不夠")
    sys.exit()
coin=[1000,500,100,50,10,5,1]
for i in coin:
    changecoin=change//i
    change=change%i
    print("你可找回{}元{}個".format(i,changecoin))
#print("你可找回{}元".format(change))