You are given a string s consisting of lowercase English letters. Extract all the characters in the odd-indexed positions and print the string obtained by concatenating them. Here, the leftmost character is assigned the index 1.

-----Constraints-----
- Each character in s is a lowercase English letter.
- 1≤|s|≤10^5

-----Input-----
The input is given from Standard Input in the following format:
s

-----Output-----
Print the string obtained by concatenating all the characters in the odd-numbered positions.

-----Sample Input-----
atcoder

-----Sample Output-----
acdr

Extract the first character a, the third character c, the fifth character d and the seventh character r to obtain acdr.

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