#include <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (n); ++i)
#define srep(i,s,t) for (int i = s; i < t; ++i)
#define drep(i,n) for(int i = (n)-1; i >= 0; --i)
using namespace std;
typedef long long int ll;
typedef pair<int,int> P;
#define yn {puts("Yes");}else{puts("No");}
#define MAX_N 200005

int main() {
    int n, l;
    cin >> n >> l;
    int ans = 0;
    int now = 0;
    rep(i,n){
        int x, w, t;
        cin >> x >> w >> t;
        ans += x - now;
        now = x;
        int amari = t*2 - (ans % (t*2));
        if(amari <= t){
            ans += amari;
            ans += w;
            now += w;
        }else{
            amari -= t;
            if(amari >= w){
                ans += w;
                now += w;
            }else{
                ans += amari + t;
                ans += w;
                now += w;
            }
        }
    }

    ans += l - now;
    cout << ans << endl;
    return 0;
}