CF1712C

package main

import (
    "bufio"
    . "fmt"
    "io"
    "os"
)

func Solve(_in io.Reader, _out io.Writer) {
    in, out := bufio.NewReader(_in), bufio.NewWriter(_out)
    defer out.Flush()
    var t, n int
    for Fscan(in, &t); t > 0; t-- {
        Fscan(in, &n)
        if n == 1 {
            Fprintln(out, 0)
            continue
        }
        a := make([]int, n)
        // 统计 a[i] 最早出现位置
        mp := map[int]int{}
        cnt := make([]int, n)
        for i := range a {
            Fscan(in, &a[i])
            cnt[i] = len(mp)
            if _, ok := mp[a[i]]; !ok {
                mp[a[i]] = i
            }
        }
        j := n-1
        for ; j >= 0; j-- {
            if j >= 1 && a[j] == a[j-1] {
                continue
            }
            if i, ok := mp[a[j]]; ok && i < j {
                break
            }
            if j >= 1 && a[j] < a[j-1] {
                break
            }
        }
        if j >= 0 {
            Fprintln(out, cnt[j])
        } else {
            Fprintln(out, 0)
        }
    }
}

func main() { Solve(os.Stdin, os.Stdout) }