number = int(input("請輸入數字:"))
count = 1
while number // 10**count > 0:
count =count +1
else:
print("這是一個 %s 位數!" % count)
==========================================
while True:
num = int(input("請輸入一個數字:"))
count = 1
while num//10 >= 0:
num = num//10
count = count + 1
print(count)