```cpp
#define int long long//__int128
tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> s;
int cnt=1,tmp=0;
int f(int k){
auto it=s.find_by_order(k-1);
if(it!=s.end()) return *it;
else return 114514;
}
signed main(){
int m,n;
cin>>m>>n;
int a[m+1],b[n+1];
for(int i=1;i<=m;i++) cin>>a[i];
for(int i=1;i<=n;i++) cin>>b[i];
for(int i=1;i<=m;i++){
s.insert(a[i]);
while(i==b[cnt]){
cnt++,tmp++;
cout<<f(tmp)<<endl;
}
}
}
```
by Jerrlee✅ @ 2022-10-07 11:13:45
[评测记录](https://www.luogu.com.cn/record/88992965)
by Jerrlee✅ @ 2022-10-07 11:14:04
是不是因为 `pb_ds` 不能重复？
by qwasd @ 2022-10-07 12:14:20
@[qwasd](/user/484970) 什么意思？麻烦具体一点谢谢
by Jerrlee✅ @ 2022-10-07 12:18:53
@[Jerrlee✅](/user/367652) 应该是某些指令c++11以下的没有
by hjsxhst2022 @ 2022-10-07 12:20:27
@[hjsxhst2022](/user/745903) 我是用 C++14 交的，应该没问题（他也没报 CE 就是
by Jerrlee✅ @ 2022-10-07 12:21:32
@[Jerrlee✅](/user/367652) `pb_ds` 的 `tree` 不能插入相同的元素
by qwasd @ 2022-10-07 12:22:16
@[Jerrlee✅](/user/367652) 没报就好
by hjsxhst2022 @ 2022-10-07 12:22:23
@[qwasd](/user/484970) 哦，我去改下试试
谢谢
by Jerrlee✅ @ 2022-10-07 12:22:53
@[Jerrlee✅](/user/367652) c++11也报错：
```cpp
/tmp/compiler_jzrhgkpo/src:2:1: 错误：‘tree’不是一个类型名
2 | tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> s;
| ^~~~
/tmp/compiler_jzrhgkpo/src: 在函数‘long long int f(long long int)’中:
/tmp/compiler_jzrhgkpo/src:5:13: 错误：‘s’在此作用域中尚未声明
5 | auto it=s.find_by_order(k-1);
| ^
/tmp/compiler_jzrhgkpo/src: 在函数‘int main()’中:
/tmp/compiler_jzrhgkpo/src:11:5: 错误：‘cin’在此作用域中尚未声明
11 | cin>>m>>n;
| ^~~
/tmp/compiler_jzrhgkpo/src:16:9: 错误：‘s’在此作用域中尚未声明
16 | s.insert(a[i]);
| ^
/tmp/compiler_jzrhgkpo/src:19:13: 错误：‘cout’在此作用域中尚未声明
19 | cout<<f(tmp)<<endl;
| ^~~~
/tmp/compiler_jzrhgkpo/src:19:27: 错误：‘endl’在此作用域中尚未声明
19 | cout<<f(tmp)<<endl;
| ^~~~
```
绝了
by hjsxhst2022 @ 2022-10-07 12:23:31