import java.io.PrintWriter
import java.util.*
import kotlin.math.*

fun PrintWriter.solve() {
    val n = nextInt()
    val counter = Array(26) { 0 }
    for (i in 0 until 26) {
        val c = 'a' + i
        val s = "$c".repeat(n)
        println("? $s")
        counter[i] = nextInt()
    }
    var ans = ""
    for (i in 0 until n) {
        val a = Array(26) { 0 }
        for (j in 0 until 26) {
            if (counter[j] == 0) continue
            val s = Array(n) { if (it == i) 'a' + j else 'a' }.joinToString("")
            println("? $s")
            a[j] = nextInt()
        }
        val j = (0 until 26).single { a[it] == a.max() }
        ans += 'a' + j
        counter[j]--
    }
    println("! $ans")
}

fun main() {
    Thread(null, {
        val writer = PrintWriter(System.out, true)
        writer.solve()
        writer.flush()
    }, "solve", abs(1L.shl(26)))
        .apply { setUncaughtExceptionHandler { _, e -> e.printStackTrace(); kotlin.system.exitProcess(1) } }
        .apply { start() }.join()
}

// region Scanner
private var st = StringTokenizer("")
private val br = System.`in`.bufferedReader()

fun next(): String {
    while (!st.hasMoreTokens()) st = StringTokenizer(br.readLine())
    return st.nextToken()
}

fun nextInt() = next().toInt()
fun nextLong() = next().toLong()
fun nextLine() = br.readLine()
fun nextDouble() = next().toDouble()
// endregion