```cpp
#include<bits/stdc++.h>
using namespace std;
int main()
{
freopen("flower.in","r",stdin);
freopen("flower.out","w",stdout);
int n,m;
cin >> n >> m;
int w[n],t[m];
for (int i = 0; i < n; i++) {
cin >> w[i];
}
for (int i = 0; i < m; i++) {
cin >> t[i];
}
for (int i = 0; i < n; i++) {
if (binary_search(t, t + m, w[i])) {
cout << w[i] << " ";
}
}
return 0;
}
```
以上为本人的代码,10个样例全WA,错误为不输出
by lxt♛♛♛ @ 2021-01-13 08:45:43
用std::set它不香吗?
by decltype_auto @ 2021-01-13 09:09:19
虽然不知道有没有binary_search这种高级库函数,但是我觉得你不排序就二分相当的离谱
by HMP_Haoge @ 2021-01-13 09:37:17
@[HMP_Haoge](/user/254036) 有的,但是的确应该先排序
by GKxx @ 2021-01-13 10:57:42
@[lxt♛♛♛](/user/352775) 调用`std::binary_search`要确保传给它的序列是有序的,不然这个函数的行为是未定义的。
by GKxx @ 2021-01-13 10:58:32
@[GKxx](/user/72071) 哦,我明白了,谢谢,奉上关注
by lxt♛♛♛ @ 2021-01-13 12:54:35