import Foundation

func getInt () -> Int64{ return Int64(readLine()!)!}
func getString() -> String { return String(readLine()!)}
func getInts() -> [Int64] {return readLine()!.components(separatedBy: " ").map{(Int64($0)!)}}
func getStrings() -> [String] {return readLine()!.components(separatedBy: " ").map{(String($0))}}
var N = getInt()
var strArray = getStrings()
var ans : [String] = []
strArray[0].map{String($0)}.forEach{ans.append($0)}
var idx = 0;
strArray[1].map{String($0)}.forEach{
    ans[idx] += $0;
    idx += 1
    
}
print(ans.reduce("",+))



