'use strict';

const main = arg => {
    const input = arg.trim().split('\n');		//Each line (l) of input is input[l]

    let ans = [], words;

    words = input[1].split(' ');

    for (var i = 0; i < Number(input[0]); i++) {

        ans.push(words[0].charAt(i));
        ans.push(words[1].charAt(i));
    }

    console.log(ans.join(''));
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'));