$1 \le n \le 5 \times 10^4$
a数组开小了
by Jason_Ming @ 2024-02-24 00:20:17
@[andyzhu444](/user/575655) 数组开大点没有事的，别吝啬自己的空间：
```
#include<bits/stdc++.h>
using namespace std;
#define int long long
int a[1000005];
unordered_map<int,bool>mp;
inline int read()
{
char c=getchar();int x=0,f=1;
for(;!isdigit(c);c=getchar())if(c=='-')f=-1;
for(;isdigit(c);c=getchar())x=x*10+c-48;
return x*f;
}
int n;
void solve(){
mp.clear();
n=read();
for(register int i=1;i<=n;i++){
a[i]=read();
if(!mp[a[i]])printf("%d ",a[i]);
mp[a[i]]=1;
}
puts("");
}
signed main(){
int k;
k=read();
for(register int i=1;i<=k;i++)solve();
}
by QuQ_ @ 2024-02-24 09:25:04
@[Jason_Ming](/user/1014421) thanks 已AC
by Chtholly_is_cute @ 2024-02-24 13:34:55