#include "bits/stdc++.h"
using namespace std;

int main() {
	int N, L;
	cin >> N >> L;
	int pos = 0;
	int time = 0;
	for (int i = 0; i < N; i++)
	{
		int X, W, T;
		cin >> X >> W >> T;
		time += X - pos;
		pos = X;

		int nexttime = (time / (2 * T)) * 2 * T;
		if (nexttime + T < time + W) time = nexttime + 2 * T;
	}

	time += L - pos;
	cout << time << endl;
}