#include<cstdio>
#include<iostream>
#include<algorithm>
#include<string>
#include<queue>
#include<vector>
#include<functional>
#include<cmath>
#include<map>
#include<stack>
#include<set>
#include<numeric>
#include<limits>

#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()

using namespace std;
typedef long long ll;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef pair<ll, string> pls;

int main()
{
	int n, l;
	cin >> n >> l;

	int s = 0, p = 0;
	for (int i = 0; i < n; i++) {
		ll x, w, t;
		cin >> x >> w >> t;

		s += x - p;
		p = x;
		if (t - w < s % (t * 2))
			s += t * 2 - s % (t * 2);
	}
	cout << s + l - p << endl;
	return 0;
}