Upper_bound vs Lower_bound in 1D and 2D in C++

	#include <iostream>
	#include <algorithm>
	#include <vector>
	using namespace std;
	int main ()
	{
	// lower_bound = start index of value
	// upper_bound = ending index of value + 1;
	int myints[] = {10, 10, 10, 20, 20, 20, 30, 30};
	std::vector<int> v(myints,myints+8);
	std::sort (v.begin(), v.end());
	std::vector<int>::iterator low,up;
	low = v.begin();
	low=std::lower_bound (v.begin(), v.end(), 10);
	up= std::upper_bound (v.begin(), v.end(), 10);
	std::cout << "lower_bound at position " << (low- v.begin()) << '\n';
	std::cout << "upper_bound at position " << (up - v.begin()) << '\n';
	cout << endl;
	vector <int> vii[10];
	vector <int> :: iterator it;
	// vii[0][0] = 1;
	// vii[0][1] = 2;
	// vii[0][2] = 3;
	// vii[0][3] = 4;
	vii[0].push_back(2);
	vii[0].push_back(4);
	vii[0].push_back(6);
	vii[0].push_back(8);
	it = lower_bound(vii[0].begin(), vii[0].end(), 4);
	std::cout << "lower_bound at position " << (it - vii[0].begin()) << '\n';
	it = upper_bound(vii[0].begin(), vii[0].end(), 4);
	std::cout << "upper_bound at position " << (it - vii[0].begin()) << '\n';
	return 0;
	}

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