Problem Description

Define a mapping from lowercase letters to 8-bit binary strings:

• Convert the ASCII code of a lowercase character into an 8-bit binary number. For example: $a \rightarrow 97 \rightarrow 01100001$.

Now A has a string $s$ of length $n$ that contains only lowercase letters. He maps this string into a binary string $t$ of length $8n$.

He shuffles the binary string $t$ and gets another binary string $t'$. Please restore one possible $s$ based on the shuffled result.

Input Format

The first line contains an integer $n$.

The second line contains a binary string $t'$ of length $8n$.

Output Format

If there is a solution, output one line containing a string $s$ of length $n$ consisting only of lowercase letters. Otherwise, output NIE.

If there are multiple solutions, output any one of them.

2
1100000011110111

ao

8
1011111010101100011011011010001010100011111111110001001001011010

potyczki

1
00011000

NIE

Hint

For $100\%$ of the testdata, $1 \leq n \leq 10^5$.

Translated by ChatGPT 5