mirror of
https://git.sb/baoshuo/OI-codes.git
synced 2024-12-25 17:12:02 +00:00
29 lines
555 B
C++
29 lines
555 B
C++
#include <iostream>
|
|
#include <unordered_map>
|
|
#include <vector>
|
|
|
|
using std::cin;
|
|
using std::cout;
|
|
using std::endl;
|
|
|
|
int n, q, a, x, k;
|
|
std::unordered_map<int, std::vector<int>> map;
|
|
|
|
int main() {
|
|
std::ios::sync_with_stdio(false);
|
|
cin >> n >> q;
|
|
for (int i = 1; i <= n; i++) {
|
|
cin >> a;
|
|
map[a].push_back(i);
|
|
}
|
|
while (q--) {
|
|
cin >> x >> k;
|
|
if (!map.count(x) || map[x].size() < k) {
|
|
cout << -1 << endl;
|
|
} else {
|
|
cout << map[x][k - 1] << endl;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|