 Helping Meesa
##### Submissions: 400   Accuracy: 17.52%   Difficulty: Easy   Marks: 2

A Lucky number is a number which has only the digits 4 and 7. Meesa makes a special function F(n) for a positive integer n  that returns all good digits of number n from the left to the right. For example, the the output for number 147 is number 47. Meesa has two numbers :

• An integer a
• A Lucky number b.

Help Meesa to find the minimum number c (c > a) such that  F(c) = b.

Input:
The first line contain T denoting the number of Test cases. Then T test cases follow . Each test case has only line contains two integers a and bIt is guaranteed that number b is lucky.

Output:
Print the number in a new line  that Meesa needs to find.

Constraints:
1 ≤ T ≤ 50
1 ≤ a, b ≤ 105

Example:
Input:

1
1 7

Output:
7

Explanation:
The minimum number x greater than 1 such that F(x) = 7 is 7 & so it is the answer.

#### ** For More Input/Output Examples Use 'Expected Output' option **

Contributor: Siddharth Dungarwal
Author: sd5869

If you have purchased any course from GeeksforGeeks then please ask your doubt on course discussion forum. You will get quick replies from GFG Moderators there.