编程介的小学生 2017-01-15 13:26 采纳率: 20.5%
浏览 956
已采纳

The Lucky Numbers

Description

John and Brus are freshmen at the primary school. Their first home task is to learn some integer numbers. It is not so hard for the guys and they decide to impress their teacher by learning all lucky numbers between A and B, inclusive.
As you already know from the previous year contest 4 and 7 are lucky digits, and all the other digits are not lucky. A lucky number is a number that contains only lucky digits in decimal notation.
After learning all lucky numbers in [A, B] range John and Brus still have some free time and now they decide to learn additionally each lucky number N that is out of [A, B] range, but the reversed number of N is in this range. Here reversed number of N is the number N written in decimal notation, but the order of digits is reversed. For example, the reversed number of 447 is 744 and reversed number of 774474444 is 444474477.
You are given integers A and B and your task is to find the total number of lucky numbers learned by John and Brus.
Input

The first line contains single integer T – the number of test cases. Each test case consists of a single line containing two integers A and B separated by a single space.
Output

For each test case print a single line containing the total number of lucky numbers learned by John and Brus.
Sample Input

2
1 100
44 47
Sample Output

6
3

  • 写回答

2条回答 默认 最新

  • threenewbee 2017-01-22 15:48
    关注
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
    评论
查看更多回答(1条)

报告相同问题?

悬赏问题

  • ¥15 按键修改电子时钟,C51单片机
  • ¥60 Java中实现如何实现张量类,并用于图像处理(不运用其他科学计算库和图像处理库))
  • ¥20 5037端口被adb自己占了
  • ¥15 python:excel数据写入多个对应word文档
  • ¥60 全一数分解素因子和素数循环节位数
  • ¥15 ffmpeg如何安装到虚拟环境
  • ¥188 寻找能做王者评分提取的
  • ¥15 matlab用simulink求解一个二阶微分方程,要求截图
  • ¥30 乘子法解约束最优化问题的matlab代码文件,最好有matlab代码文件
  • ¥15 写论文,需要数据支撑