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 Go (1.6) (judge verdict: Accepted)

package main

import (
	"fmt"
	"unicode/utf8"
	"strings"
)

func main(){
	var s string
	fmt.Scan(&s)
	l := utf8.RuneCountInString(s)
	sl := make([]string,l)
	sl = strings.Split(s,"")
	var w int
	fmt.Scan(&w)
	for i:= 0; i < len(sl); i += w{
		fmt.Print(sl[i])
	}
}