#include<bits/stdc++.h>
using namespace std;
const int N=1e6+5;
int n,t[N],vis[N];
void solve() {
	scanf("%d",&n);
	for(int i=1,x;i<=n;i++)scanf("%d",&x),t[i]=i-x,vis[i]=0;
	int x=1,ct=0;do vis[x]=++ct,x=t[x];while(!vis[x]);
	printf("%d\n",ct-vis[x]+1);
	for(int i=1;i<=n;i++)if(vis[i]>=vis[x])printf("%d ",i);puts("");
}
int main() {
	int tt;scanf("%d",&tt);
	while(tt--)solve();
	return 0;
}