Problem:
Score : 200 points

Problem Statement

Given are strings s and t of length N each, both consisting of lowercase English letters.

Let us form a new string by alternating the characters of S and the characters of T, as follows: the first character of S, the first character of T, the second character of S, the second character of T, ..., the N-th character of S, the N-th character of T. Print this new string.

Constraints

1 \leq N \leq 100

|S| = |T| = N

S and T are strings consisting of lowercase English letters.

Input

Input is given from Standard Input in the following format:

N
S T

Output

Print the string formed.

Sample Input 1

2
ip cc

Sample Output 1

icpc

Sample Input 2

8
hmhmnknk uuuuuuuu

Sample Output 2

humuhumunukunuku

Sample Input 3

5
aaaaa aaaaa

Sample Output 3

aaaaaaaaaa

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

#include <stdio.h>
#include <string.h>

int main(int argc, char const *argv[]) {

  char cN[5];
  int N;
  fgets(cN, 5, stdin);
  sscanf(cN, "%d", &N);

  //printf("N = %d\n", N);

  char str1[120];
  //fgets(str1, sizeof(str1), stdin);

  char str2[120];
  //fgets(str2, sizeof(str2), stdin);

  char strb[250];
  fgets(strb, 250, stdin);
  sscanf(strb, "%s %s", str1, str2);

  //printf("str1 = %s\n", str1);
  //printf("str2 = %s\n", str2);

  /*
  for (int i = 0; i < 100; i++) {
    str1[i] = 'a';
    str2[i] = 'b';
  }
  */

  char str3[250];

  for (int i = 0; i < N; i++) {
    //printf("str1[%d] = %c\n", i, str1[i]);
    //printf("str2[%d] = %c\n", i, str2[i]);
    str3[2 * i] = str1[i];
    str3[2 * i + 1] = str2[i];
    //printf("str3[%d] = %c\n", 2 * i, str3[2 * i]);
    //printf("str3[%d] = %c\n", 2 * i + 1, str3[2 * i + 1]);
  }

  printf("%s\n", str3);

  return 0;

}