第三次作业

自己实现扫描全盘的函数

def scan_disk(dir):
    global count,dir_count
    if os.path.isdir(dir):
        files = os.listdir(dir)
        for file in files:
            print(file)
            dir_count += 1
            if os.path.isdir(dir + os.sep + file):
                scan_disk(file)
            else:
                count += 1
scan_disk("D:")
print("file_count",count)
print("dircount",count)

def is_zhishu(num):
    for i in range(2, num // 2 + 1):
        if num % i == 0:
            return False
 
    return True

 
def is_huiwenshu(num):
    if str(num) == str(num)[::-1]:
        return True
 
 
count = 0
num = 2
while count < 100:
    if is_zhishu(num) and is_huiwenshu(num):
        print("%5d" % num, end=" ")
        count += 1
 
        if count % 10 == 0:
            print()
    num += 1

def isValid(side1, side2, side3):
    return side1 + side2 > side3 and side2 + side3 > side1 and side1 + side3 > side2
 
 
def area(side1, side2, side3):
    s = (side1 + side2 + side3) / 2
    return (s * (s - side1) * (s - side2) * (s - side3)) ** 0.5
 
 
s1, s2, s3 = eval(input("请输入三角形三边长:"))
if isValid(s1, s2, s3):
    print("area is %.2f" % area(s1, s2, s3))
else:
    print("Invalid")