package main

import (
	"bufio"
	"fmt"
	"os"
)

type FastScanner struct {
	r *bufio.Reader
}

func NewFastScanner() *FastScanner {
	return &FastScanner{r: bufio.NewReaderSize(os.Stdin, 1<<20)}
}

func (fs *FastScanner) NextInt() int {
	sign, val := 1, 0
	c, err := fs.r.ReadByte()
	for (c < '0' || c > '9') && c != '-' {
		c, err = fs.r.ReadByte()
		if err != nil {
			return 0
		}
	}
	if c == '-' {
		sign = -1
		c, _ = fs.r.ReadByte()
	}
	for c >= '0' && c <= '9' {
		val = val*10 + int(c-'0')
		c, err = fs.r.ReadByte()
		if err != nil {
			break
		}
	}
	if err == nil {
		_ = fs.r.UnreadByte()
	}
	return sign * val
}

func main() {
	in := NewFastScanner()
	out := bufio.NewWriterSize(os.Stdout, 1<<20)
	defer out.Flush()

	t := in.NextInt()
	for ; t > 0; t-- {
		n := in.NextInt()
		x := make([]int, n+1)
		seen := make([]bool, n+1)
		pos1, posN := -1, -1
		for i := 1; i <= n; i++ {
			x[i] = in.NextInt()
			seen[x[i]] = true
			if x[i] == 1 {
				pos1 = i
			}
			if x[i] == n {
				posN = i
			}
		}

		missing := -1
		for v := 1; v <= n; v++ {
			if !seen[v] {
				missing = v
				break
			}
		}

		if missing != -1 {
			other := 1
			if other == missing {
				other = 2
			}
			fmt.Fprintf(out, "? %d %d\n", missing, other)
			out.Flush()
			ans := in.NextInt()
			if ans == -1 {
				return
			}
			if ans == 0 {
				fmt.Fprintln(out, "! A")
			} else {
				fmt.Fprintln(out, "! B")
			}
			out.Flush()
		} else {
			fmt.Fprintf(out, "? %d %d\n", pos1, posN)
			out.Flush()
			d1 := in.NextInt()
			if d1 == -1 {
				return
			}
			fmt.Fprintf(out, "? %d %d\n", posN, pos1)
			out.Flush()
			d2 := in.NextInt()
			if d2 == -1 {
				return
			}
			if d1 < n-1 || d2 < n-1 {
				fmt.Fprintln(out, "! A")
			} else {
				fmt.Fprintln(out, "! B")
			}
			out.Flush()
		}
	}
}