HDU 5676

Problem Description

ztr loves lucky numbers. Everybody knows that positive integers are lucky if their decimal representation doesn't contain digits other than 4 and 7. For example, numbers 47, 744, 4 are lucky and 5, 17, 467 are not.

Lucky number is super lucky if it's decimal representation contains equal amount of digits 4 and 7. For example, numbers 47, 7744, 474477 are super lucky and 4, 744, 467 are not.

One day ztr came across a positive integer n. Help him to find the least super lucky number which is not less than n.

 

Input

There are T (1≤n≤105) cases

For each cases:

The only line contains a positive integer  n(1≤n≤1018). This number doesn't have leading zeroes.

 

Output

For each cases
Output the answer

 

Sample Input

2 4500 47

 

Sample Output

4747 47

 

题意：问最小的大于等于n的数，并且这个数只由4和7组成，且4和7的个数一样。

思路：直接将1~16位的所有数通过dfs打表得到，奇数位的n的答案肯定是位数加1的合法的数，但是当n大于16位最大的合法数的时候，答案是爆long long，通过特判输出。

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