#include <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (n); i++)
using namespace std;
typedef long long ll;

int main(){
    cin.tie(0);
    ios::sync_with_stdio(0);
    
    ll N,L; cin >> N >> L;
    ll pos = 0, now = 0;
    rep(_,N) {
        ll X,W,T; cin >> X >> W >> T;
        now += X - pos;
        // [0, T) [T, 2T)
        if(now % (2 * T) < T && (now + W) % (2 * T) < T) {
            now += W;
        } else {
            now = (now + (2 * T) - 1) / (2 * T) * (2 * T);
            now += W;
        }
        pos = X + W;
    }
    now += L - pos;
    pos = L;
    cout << now << endl;
}