#include <iostream>
using namespace std;
int n;
int arr[11451400];
void solve()
{
}
int main()
{
    int T;
    cin >> T;
    while (T--)
    {
         cin >> n;
        for (int i = 1;i <= n; i++)
        {
            cin >> arr[i];
        }
        long long l = 1, r = n;
        long long maxest = n, minnest = 1;
        while (1)
        {
            if (l > r)
            {
                cout << "-1\n";
                goto nos;
            }
        
            if (arr[l] = maxest)
            {
                l++;
                maxest--;
                continue;
            }
            if (arr[l] == minnest)
            {
                l++;
                minnest++;
                continue;
            }
            if (arr[r] == maxest)
            {
                r--;
                maxest--;
                continue;
            }
            if (arr[r] == minnest)
            {
                r--;
                minnest++;
                continue;
            }
            break;
        }
        cout << l << " " << r << "\n";
        nos:;
    }
}

感觉都快和题解一模一样了，结果样例 WA……

题目编号：CF1793C