#include <iostream>
#include <cstdio>
using namespace std;
 
int main() {
	int t, n, m, a[10005], b[10005], c[1005], d[10005];
	scanf("%d", &t);
	while(t--) {
		for(int i=0; i<10005; i++) a[i]=b[i]=d[i]=0;
		for(int i=0; i<1005; i++) c[i]=0;
		scanf("%d%d", &n, &m);
		for(int i=0; i<m; i++) scanf("%d%d", &a[i], &b[i]);
		for(int i=m-1; i>=0; i--) if(c[a[i]]==0 && c[b[i]]==0) d[i]++, c[a[i]]++, c[b[i]]++;
		for(int i=0; i<m; i++) if(d[i]) printf("%d ", i);
		printf("\n");
	}
	return 0;
}

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Mgo0IDUKMCAxCjEgMgoyIDMKMSAzCjMgMAo0IDMKMCAxCjIgMwoyIDE=

2
4 5
0 1
1 2
2 3
1 3
3 0
4 3
0 1
2 3
2 1