Submission #3786254

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Source Code Expand

A, B = input().split()
if int(A) < int(B):
  A, B = B, A
base = [0] * 20
for i in range(1, 19):
  base[i] = 2 * 10 ** (i - 1) + 8 * base[i - 1]
def forbidden(N):
  cnt = 0
  for i, n in enumerate(N):
    n = int(n)
    if n < 4:
      cnt += base[len(N) - i - 1] * n
    elif n == 4:
      cnt += base[len(N) - i - 1] * 3 + int(N[i + 1:]) + 1
      break
    elif n < 9:
      cnt += base[len(N) - i - 1] * (n - 2) + 10 ** (len(N) - i - 1)
    elif n == 9:
      cnt += base[len(N) - i - 1] * 7 + 10 ** (len(N) - i - 1) + int(N[i + 1:] if i < len(N) - 1 else 0) + 1
      break
  return cnt
print(forbidden(A) - forbidden(B) + (1 if '4' in B or '9' in B else 0))

Submission Info

Judge Result