记录

#include<iostream>
#include<cstring>
using namespace std;
const int maxn = 2*1e5 + 10;
bool vin[maxn];
int main(){
	int T; scanf("%d", &T);
	while(T--){;
		memset(vin, 0, sizeof vin);
		int m,n,cnt = 0,deux = 0;scanf("%d%d", &n, &m);
		bool done = 0;
		for(int i = 1; i <= m; i++){
			int o, x;scanf("%d%d", &o, &x);
			if(done) continue;
			if(o-1){
				if(vin[x]){ printf("%d\n", i);done=1;}
				else if(deux && deux != x){ printf("%d\n", i);done=1;}
				deux = x;
			}
			else if(!vin[x]){
				vin[x] = 1;
				cnt++;
				if(deux == x){ printf("%d\n", i);done=1;}
				if(cnt == n){ printf("%d\n", i);done=1;}
			}
		}
		if(!done) printf("-1\n");
	}
	return 0;
}