#include <iostream>
#include <vector>

using namespace std;

int main() {
	int n, l;
	cin >> n >> l;
	vector<int> x(n + 1), w(n + 1), t(n + 1);
	for (int i = 0; i < n; ++i) {
		cin >> x[i + 1] >> w[i + 1] >> t[i + 1];
	}
	int elapsed = 0;
	for (int i = 1; i < n + 1; ++i) {
		elapsed += x[i] - (x[i - 1] + w[i - 1]);
		int timing = elapsed % (t[i] * 2);
		if (timing + w[i] - 1 >= t[i]) {
			elapsed += t[i] * 2 - timing;
		}
		elapsed += w[i];
	}
	elapsed += l - (x.back() + w.back());
	cout << elapsed << endl;
	return 0;
}