백준 2910번 c++ map활용

#include <bits/stdc++.h>
using namespace std;

int main() {
	cin.tie(0)->sync_with_stdio(0);
	int n, c;
	cin >> n >> c;
	int arr[1005];
	for (int i = 0; i < n; i++) {
		cin >> arr[i];
	}
	map <int, int> mp, fr;

	for (int i = 0; i < n; i++) {
		mp[arr[i]]++;
		if (!fr.count(arr[i])) {
			fr[arr[i]] = i;
		}
	}
	sort(arr, arr + n, [&](int x, int y) {return pair<int, int>(mp[x],
		-fr[x]) > pair<int, int>(mp[y], -fr[y]); });
	for (int i = 0; i < n;i++) {
		cout << arr[i] << " ";
	}
	return 0;
}