function main(arg) {
    const lines = arg.split("\n");
    const N = parseInt(lines[0]);
    const ST = lines[1].split(" ");
    const S = ST[0]
    const T = ST[1]

    let answer = "";
    for (var i = 0; i < N; i++) {
        answer += S[i] + T[i]
    }
    console.log(answer)
}

main(require('fs').readFileSync('/dev/stdin', 'utf8'));