题解 | #查找#

#include<bits/stdc++.h>
using namespace std;
int main(){
	set<int>s;
	//write your code here......
	int n, m;
	cin >> n >> m;

	int num;

	for (int i{0}; i < n; i++) {
		cin >> num;
		s.insert(num);
	}

	vector<int> w;
	for (int i{0}; i < m; i++) {
		cin >> num;
		w.push_back(num);
	}

	for (auto& item: w) {
		auto pr {s.equal_range(item)};
		if (pr.second != s.end())
			cout << *pr.second << endl;
		else {
			cout << -1 << endl;
		}
	}

	return 0;
}