#include "testlib.h"
#include <bits/stdc++.h>
using namespace std;
using ll = long long;

const int Nmin = 1, Nmax = 5000;
const int Kmin = 0, Kmax = 1'000'000'000;

int main(){
	registerValidation();
	int N = inf.readInt(Nmin, Nmax);
	inf.readSpace();
	int K = inf.readInt(Kmin, Kmax);
	inf.readEoln();

	ll Xmin = 0;
	ll Xmax = (ll)N * K;
	for (int i=1; i<=N; i++){
		int Rmin = i;
		int Rmax = N;
		inf.readInt(Rmin, Rmax);
		inf.readSpace();
		inf.readLong(Xmin, Xmax);
		inf.readEoln();
	}
	inf.readEof();
}