Score: $300$ points
Mr. Infinity has a string $S$ consisting of digits from 1 to 9. Each time the date changes, this string changes as follows:
2 in $S$ is replaced with 22. Similarly, each 3 becomes 333, 4 becomes 4444, 5 becomes 55555, 6 becomes 666666, 7 becomes 7777777, 8 becomes 88888888 and 9 becomes 999999999. 1 remains as 1.For example, if $S$ is 1324, it becomes 1333224444 the next day, and it becomes 133333333322224444444444444444 the day after next.
You are interested in what the string looks like after $5 \times 10^{15}$ days. What is the $K$-th character from the left in the string after $5 \times 10^{15}$ days?
Input is given from Standard Input in the following format:
$S$ $K$
Print the $K$-th character from the left in Mr. Infinity's string after $5 \times 10^{15}$ days.
1214 4
2
The string $S$ changes as follows:
121412214444122221444444444444444412222222214444444444444444444444444444444444444444444444444444444444444444The first five characters in the string after $5 \times 10^{15}$ days is 12222. As $K=4$, we should print the fourth character, 2.
3 157
3
The initial string is 3. The string after $5 \times 10^{15}$ days consists only of 3.
299792458 9460730472580800
2