#include <iostream>
#include <vector>
#include <cmath>
#include <iomanip>
using namespace std;
int main()
{
int n, m;
cin >> n >> m;
vector<vector<double>> T(n, vector<double>(2));
for (int i = 0; i < n; ++i) // for循环比foreach易读性强
{
cin >> T[i][0] >> T[i][1];