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, m := in.NextInt(), in.NextInt()
		seen := make([]bool, n+m+1)
		uniqueTimes := make([]int, 0, m)
		for i := 1; i <= m; i++ {
			p := in.NextInt()
			if !seen[p] {
				seen[p] = true
				uniqueTimes = append(uniqueTimes, i)
			}
		}
		for i := 1; i <= n; i++ {
			k := n - i + 1
			ans := -1
			if k <= len(uniqueTimes) {
				ans = uniqueTimes[k-1]
			}
			if i > 1 {
				fmt.Fprint(out, " ")
			}
			fmt.Fprint(out, ans)
		}
		fmt.Fprintln(out)
	}
}