Problem:
Score : 200 points

Problem Statement

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 1

atcoder

Sample Output 1

acdr

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

Sample Input 2

aaaa

Sample Output 2

aa

Sample Input 3

z

Sample Output 3

z

Sample Input 4

fukuokayamaguchi

Sample Output 4

fkoaaauh

Solution in C++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <bits/stdc++.h>
using namespace std;

#ifdef LOCAL
#define debug(var) cerr << #var << " = " << var << endl;
#else
#define debug(var)
#endif

void init() {
	ios_base::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);
}

void solve() {
	string s; cin >> s;
	for (int i = 0; i < (int)s.size(); ++i) {
		if (i%2) continue;
		cout << s[i];
	}
}

int main() {
	init();
	int t = 1; //scanf("%d", &t);
	while (t--) {
		solve();
	}
	return 0;
}