function main(input) {
    var arr1 = input.split('\n')
    var n = arr1[0]
    var arr2 = arr1[1].split(' ')
    var s = arr2[0]
    var t = arr2[1]
    
    var acc = ''
    for(var i = 0; i < n; i++){
        acc += s[i]
        acc += t[i]
    }
    console.log(acc)
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'));