#54157: C++可以用 unordered_map
hch980506@gmail.com
(申有娜我老婆)
#include <iostream>
#include <unordered_map>
#include <vector>
using namespace std;
int main() {
int n, k;
cin >> n >> k;
vector<int> num(n);
unordered_map<int, int> pos;
for (int i = 0; i < n; i++) {
cin >> num[i];
pos[num[i]] = i + 1;
}
while (k--) {
int temp;
cin >> temp;
if (pos.count(temp)) {
cout << pos[temp] << '\n';
} else {
cout << "0\n";
}
}
}