how to make a vector of pairs code example

Example 1: vector of pairs declaration in cpp

vector<pair<int,int>>v;

Example 2: vector of vectors of pairs c++

vector<vector<pair<int, float>>> vec(10, vector<pair<int, float>>(5, pair<int, float>(0, 0)));

	for (int i = 0; i < vec.size(); i++)
	{
		for (int j = 0; j < vec[i].size(); j++)
		{
			cout << vec[i][j].first << " ";
			cout << vec[i][j].second << " ";
		}
		cout << endl;
	}