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 WHOLE(v) (v).begin(), (v).end()
#define REV_WHOLE(v) (v).rbegin(), (v).rend()
using i64 = int64_t;
using namespace std;
template<size_t I,class H,class...T>struct TupleReaderWriter{static tuple<H,T...> r(istream&i){H v;i>>v;return tuple_cat(tuple<H>(v),TupleReaderWriter<sizeof...(T)-1,T...>::r(i));}static void w(ostream&o,tuple<H,T...>&t,string d){TupleReaderWriter<I-1,H,T...>::w(o,t,d);o<<d<<get<I>(t);}};
template<class H,class...T>struct TupleReaderWriter<0,H,T...>{static tuple<H,T...> r(istream&i){H v;i>>v;return tuple<H>(v);}static void w(ostream&o,tuple<H,T...>&t,string d){o<<get<0>(t);}};
template<class...T>istream&operator>>(istream&i,tuple<T...>&t){t=TupleReaderWriter<sizeof...(T),T...>::r(i);return i;}
template<class...T>ostream&operator<<(ostream&o,tuple<T...>&t){string delim=" ";TupleReaderWriter<sizeof...(T)-1,T...>::w(o,t,delim);return o;}
template<class T>istream&operator>>(istream&i,vector<T>&v){for(auto&x:v)i>>x;return i;}
template<class T>ostream&operator<<(ostream&o,vector<T>&v){string delim="";for(auto&x:v)o<<delim<<x,delim=" ";return o;}
template<class T>using rev_priority_queue=priority_queue<T,vector<T>,greater<T>>;
template<class T>using vector2d=vector<vector<T>>;
struct fixprec{int x;fixprec(int d):x(d){}};
ostream&operator<<(ostream&o,fixprec f){return o<<fixed<<setprecision(f.x);}
void R_YESNO(bool p) { cout << (p ? "YES" : "NO") << endl; }
void R_YesNo(bool p) { cout << (p ? "Yes" : "No") << endl; }
int main() {
    int N;
    cin >> N;
    string S, T, ans;
    cin >> S >> T;
    for(int i = 0; i < N; i++) {
        ans += S[i];
        ans += T[i];
    }
    cout << ans << endl;
    return 0;
}