Two Lucky Numbers

AtCoder
IDarc131_a
Time2000ms
Memory256MB
Difficulty
Mr. AtCoder reads in the newspaper that today's lucky number is a positive integer $A$ and tomorrow's is a positive integer $B$. Here, he defines a positive integer $x$ that satisfies both of the following conditions as a super-lucky number. * The decimal notation of $x$ contains $A$ as a contiguous substring. * The decimal notation of $2x$ contains $B$ as a contiguous substring. Actually, under the Constraints of this problem, there is always a super-lucky number less than $10^{18}$. Find one such number. ## Constraints * $1 \leq A < 10^8$ * $1 \leq B < 10^8$ * $A$ and $B$ have no leading `0`s. * All values in input are integers. ## Input Input is given from Standard Input in the following format: $A$ $B$ [samples]
Samples
Input #1
13
62
Output #1
131

One super-lucky number is $x = 131$, because:

*   $x = 131$ contains $13$ as a substring. ($1$\-st through $2$\-nd characters)
*   $2x = 262$ contains $62$ as a substring. ($2$\-nd through $3$\-rd characters)

Some other super-lucky numbers are $313$, $8135$, and $135797531$, which would also be accepted.
Input #2
69120
824
Output #2
869120

One super-lucky number is $x = 869120$, because:

*   $x = 869120$ contains $69120$ as a substring. ($2$\-nd through $6$\-th characters)
*   $2x = 1738240$ contains $824$ as a substring. ($4$\-th through $6$\-th characters)

The smallest super-lucky number is $69120$, but note that any lucky number with at most $18$ digits would be accepted.
Input #3
6283185
12566370
Output #3
6283185

When $x = 6283185$, $x$ is $A$ itself, and $2x$ is $B$ itself. In such a case too, $x$ is a super-lucky number.
API Response (JSON)
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    "platform": "AtCoder",
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      "statement_type": "Markdown",
      "content": "Mr. AtCoder reads in the newspaper that today's lucky number is a positive integer $A$ and tomorrow's is a positive integer $B$.\nHere, he defines a positive integer $x$ that satisfies both of the foll...",
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