A10440. Restore a Number

Vasya decided to pass a very large integer $n$ to Kate. First, he wrote that number as a string, then he appended to the right integer $k$ — the number of digits in $n$ .

Magically, all the numbers were shuffled in arbitrary order while this note was passed to Kate. The only thing that Vasya remembers, is a non-empty substring of $n$ (a substring of $n$ is a sequence of consecutive digits of the number $n$ ).

Vasya knows that there may be more than one way to restore the number $n$ . Your task is to find the smallest possible initial integer $n$ . Note that decimal representation of number $n$ contained no leading zeroes, except the case the integer $n$ was equal to zero itself (in this case a single digit 0 was used).

The first line of the input contains the string received by Kate. The number of digits in this string does not exceed $1000000$ .

The second line contains the substring of $n$ which Vasya remembers. This string can contain leading zeroes.

It is guaranteed that the input data is correct, and the answer always exists.

Print the smalles integer $n$ which Vasya could pass to Kate.