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++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <bits/stdc++.h>

#define REP(i, e) for(int (i) = 0; (i) < (e); ++(i))
#define FOR(i, b, e) for(int (i) = (b); (i) < (e); ++(i))
#define ALL(c) (c).begin(), (c).end()
#define ACC(c) (accumulate(ALL(c), 0LL))
#define PRINT(x) cout << (x) << "\n"

using namespace std;
using ll = long long;
using pint = pair<int, int>;
using pll = pair<ll, ll>;

inline int std_in(int& a) {return scanf("%d", &a);}
auto pint_compare = [](pint x, pint y) -> bool{return (x.first < y.first);};
const int MOD = 1000000007;


signed main(){
    int N;
    string S, T;
    cin >> N >> S >> T;
    string U = "";
    REP(i, N){
        U = U + S[i];
        U = U + T[i];
    }
    PRINT(U);
    return 0;
}