const int maxn=2e5+7,maxm=2e5+7;
ll n;
ll h[maxn],e[maxm],ne[maxm],idx,f[maxn],w[maxn];
ll dfn[maxn],low[maxn],timetamp,belong[maxn];
stack<int>stk;
bool st[maxn];
ll scc_cnt;
void init(){
  memset(h,-1,sizeof h);
  memset(w,0,sizeof w);
  memset(dfn,0,sizeof dfn);
  memset(low,0,sizeof low);
  memset(belong,0,sizeof belong);
  memset(st,0,sizeof st);
  idx=scc_cnt=timetamp=0;
}
void add(ll a,ll b){
    e[idx]=b,ne[idx]=h[a],h[a]=idx++;
}
void tarjan(int u){
    dfn[u]=low[u]=++timetamp;
    stk.push(u);st[u]=1;
    for(int i=h[u];~i;i=ne[i]){
        int j=e[i];
        if(!dfn[j]){
            tarjan(j);
            low[u]=min(low[u],low[j]);
        }
        else if(st[j]) low[u]=min(low[u],dfn[j]);
    }
    if(dfn[u]==low[u]){
        ++scc_cnt;
        int y;
        do{
            y=stk.top();
            stk.pop();
            belong[y]=scc_cnt;
            st[y]=0;
        }while(y!=u);
    }
}
vector<int>g[maxn];
int main(){
  int _=read;
  while(_--){
    init();
    n=read;
    rep(i,1,n){
      f[i]=read;
      add(i,f[i]);
      g[i].clear();
    }
    rep(i,1,n) if(!dfn[i]) tarjan(i);
    rep(i,1,n) 
      w[belong[i]]+=f[i],g[belong[i]].push_back(i);
    ll resp=-1,resq=-1,flag=1;
    vector<int>v;
    rep(i,1,scc_cnt){
      if(g[i].size()==1){
        if(g[i][0]==f[g[i][0]]){
          if(resp==-1){
            resp=1,resq=w[i];
          }
          else{
            if(resp*w[i]!=resq*1){
              flag=0;break;
            }
          }
        }
      }
      else if(g[i].size()>1) {
        if(resp==-1){
            resp=g[i].size(),resq=w[i];
          }
          else{
            if(resp*w[i]!=resq*g[i].size()){
              flag=0;break;
            }
          }
      }
    }
    if(flag) puts("YES");
    else puts("NO");    
  }
  return 0;
}