2542. Decode the Strings

单点时限: 2.0 sec

内存限制: 256 MB

Bruce Force has had an interesting idea how to encode strings. The following is the description of how the encoding is done:

Let x1,x2,…,xn be the sequence of characters of the string to be encoded.

Choose an integer m and n pairwise distinct numbers p1,p2,…,pn from the set {1, 2, …, n} (a permutation of the numbers 1 to n).

Repeat the following step m times.

For 1 ≤ i ≤ n set yi to xpi, and then for 1 ≤ i ≤ n replace xi by yi.

For example, when we want to encode the string “hello”, and we choose the value m = 3 and the permutation 2, 3, 1, 5, 4, the data would be encoded in 3 steps: “hello” -> “elhol” -> “lhelo” -> “helol”.

Bruce gives you the encoded strings, and the numbers m and p1, …, pn used to encode these strings. He claims that because he used huge numbers m for encoding, you will need a lot of time to decode the strings. Can you disprove this claim by quickly decoding the strings?

输入格式

The input contains several test cases. Each test case starts with a line containing two numbers n and m (1 ≤ n ≤ 80, 1 ≤ m ≤ 10^9). The following line consists of n pairwise different numbers p1,…,pn (1 ≤ pi ≤ n). The third line of each test case consists of exactly n characters, and represent the encoded string. The last test case is followed by a line containing two zeros.

输出格式

For each test case, print one line with the decoded string.

样例

Input
5 3
2 3 1 5 4
helol
16 804289384
13 10 2 7 8 1 16 12 15 6 5 14 3 4 11 9
scssoet tcaede n
8 12
5 3 4 2 1 8 6 7
encoded?
0 0
Output
hello
second test case
encoded?

8 人解决,18 人已尝试。

12 份提交通过,共有 61 份提交。

7.4 EMB 奖励。

创建: 15 年,8 月前.

修改: 7 年,2 月前.

最后提交: 1 年,4 月前.

来源: Ulm Local 2008

题目标签