题解 | 自守数

while True:
    try:
        num = int(input())
        lstA,lstB = [],[]
        count = 0
        for i in range(0,num+1):
            lstA = list(str(i))
            lstB = list(str(i**2))
            if lstA == lstB[-len(lstA):]:
                count +=1
        print(count)
    except:
        break