Problem:
Score : 200 points

Problem Statement

You are given a string S consisting of lowercase English letters.
We will write down this string, starting a new line after every w letters. Print the string obtained by concatenating the letters at the beginnings of these lines from top to bottom.

Constraints

1 \leq w \leq |S| \leq 1000

S consists of lowercase English letters.

w is an integer.

Input

Input is given from Standard Input in the following format:

S
w

Output

Print the desired string in one line.

Sample Input 1

abcdefgh
3

Sample Output 1

adg

When we write down abcdefgh, starting a new line after every three letters, we get the following:

abc

def

gh

Concatenating the letters at the beginnings of these lines, we obtain adg.

Sample Input 2

lllll
1

Sample Output 2

lllll

Sample Input 3

souuundhound
2

Sample Output 3

suudon

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

#include <stdio.h>

int main(int argc, char const *argv[]) {
	char str[1002] = {0};
	int w;
	char buf[1001] = {0};

	fgets(str, 1001, stdin);
	// sscanf(str, "%d\n", &n, &m);
	scanf("%d\n", &w);

	int i;
	for (i = 0; str[i] != 0;i+=w) {
		printf("%c", str[i]);
	}
	printf("\n");

	return 0;
}