@[hehe123313](/user/1091535)
仔细读题。
> 第 $1$ 行为 $1$ 个正整数 $M$，表示不相同的随机数的个数。
by One_JuRuo @ 2023-11-21 16:05:00
```cpp
#include<bits/stdc++.h>
using namespace std;
int n;
set <int> st;
int main(){
cin>>n;
for(int i=1;i<=n;i++){
int x;
cin>>x;
st.insert(x);
}
cout<<st.size()<<endl;
for(auto it:st){
cout<<it<<' ';
}
return 0;
}
```
by StenvenPig @ 2023-12-02 15:25:23
```cpp
#include <bits/stdc++.h>
using namespace std;
set<int> s;
int main () {
int n;
int num;
cin >> n;
for (int i = 0; i < n; i++) {
cin >> num;
s.insert(num);
}
cout << s.size() << endl;
while (s.empty() == 0) {
cout << *s.begin() << ' ';
s.erase(s.begin());
}
return 0;
}
```
by SmileMaker @ 2023-12-24 10:52:25