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29 lines
555 B
C++
29 lines
555 B
C++
#include <iostream>
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#include <unordered_map>
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#include <vector>
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using std::cin;
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using std::cout;
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using std::endl;
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int n, q, a, x, k;
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std::unordered_map<int, std::vector<int>> map;
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int main() {
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std::ios::sync_with_stdio(false);
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cin >> n >> q;
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for (int i = 1; i <= n; i++) {
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cin >> a;
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map[a].push_back(i);
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}
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while (q--) {
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cin >> x >> k;
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if (!map.count(x) || map[x].size() < k) {
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cout << -1 << endl;
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} else {
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cout << map[x][k - 1] << endl;
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}
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}
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return 0;
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}
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