31 int a[20];32 int dp[20][2];33 34 int dfs(int pos, int pre, int sta, bool limit) {35     if (pos == -1) return 1;36     if (!limit && dp[pos][sta] != -1) return dp[pos][sta];37     int up = limit ? a[pos] : 9;38     int res = 0;39     rep(i, 0, up + 1) {40         if (i == 2 && pre == 6) continue;41         if (i == 4) continue;42         res += dfs(pos - 1, i, i == 6, limit && i == a[pos]);43     }44     if (!limit) dp[pos][sta] = res;45     return res;46 }47 48 int solve(int x) {49     int pos = 0;50     while (x) {51         a[pos++] = x % 10;52         x /= 10;53     }54     return dfs(pos - 1, -1, 0, true);55 }56 57 int main() {58     ios::sync_with_stdio(false), cin.tie(0);59     int l, r;60     while (cin >> l >> r, l + r) {61         memset(dp, -1, sizeof(dp));62         cout << solve(r) - solve(l - 1) << endl;63     }64     return 0;65 }