代码如下：

# include <bits/stdc++.h>
using namespace std;

bool a[200005];
int main(){
	int T;
	cin >> T;
	while(T--)
	{
		int n, m, ans = 0, t = 0, cot = 0;
		cin >> n >> m;
		
		memset(a, 0, sizeof(a));
		
		for(int i = 1; i <= m; i++)
		{
			int d, s;
			cin >> d >> s;
			t++;
			if(d == 1)
			{
				if(a[s] == 0)
				{
					a[s] = 1;
					cot++;
				} 
			}
			else
			{
				if(a[s] == 1)
				{
					ans = t;
					break;
				}
				else
				{
					cot = n - 1;
				}
			}
			if(cot == n)
			{
				ans = t;
				break;
			}
		}
		if(cot == n)
		{
			cout << ans << endl;
		}
		else
		{
			cout << -1 << endl;
		}
	}
	return 0;
}