#include <iostream>
#include <vector>
#include <algorithm>
 
using namespace std;
 
struct compareFirstPairMember {
    bool operator()(const pair<int, int>& a, const pair<int, int>& b) const {
        return a.first < b.first;
    }
};
 
int main() {
 
	vector<pair<int, int>> v;
	v.push_back(pair<int,int>(3,600));
    v.push_back(pair<int,int>(2,900));
    v.push_back(pair<int,int>(2,800));
 
	sort(v.begin(), v.end(), compareFirstPairMember());
 
	do {
		for(auto item : v)
          cout << item.first << " " << item.second << endl;
        cout << endl;
    } while ( std::next_permutation(begin(v), end(v), [](const pair<int, int>& a, const pair<int, int>& b) { return a.first < b.first; }));
 
	return 0;
}

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