while True: try: n = int(input()) if n<1 or n>10000: break count = 0 for i in range(0,n+1): # 获得平方数的字符串 pf = str(i*i) # 获得i的长度 len_i = len(str(i)) # 获得平方的长度 len_pf = len(pf) if str(i) in pf[(len_pf-len_i)::1]: count +=1 print(count)

except:
    break

while input()=='1':

s = str(25)

print(s[1::1])

print('5' in s[1::1])

break