这样改一下
```cpp
#include <bits/stdc++.h>
using namespace std;
struct line{
int num,index;
}a[100001];
bool cmp(line x,line y){
return x.num<y.num;
}
int n,q,x;
int main() {
cin>>n;
for(int i=1;i<=n;i++){
cin>>a[i].num;
a[i].index=i;
}
sort(a+1,a+n+1,cmp);
cin>>q;
while(q--){
cin>>x;
int l=1,r=n+1;
while(l<r){
int mid=(l+r)/2;
if(a[mid].num>x) r=mid;
else if(a[mid].num<x) l=mid+1;
else{
cout<<a[mid].index<<endl;
break;
}
}
if(l>=r)cout<<"0\n";
}
return 0;
}
```
by QZLY @ 2023-08-12 14:20:26
@[QZLY](/user/565885) AC了，谢谢
by QZLY @ 2023-08-12 14:20:53