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

signed main(){
  int n,l;cin>>n>>l;
  int nowt=0,nowp=0;
  while(n--){
    int x,w,t;cin>>x>>w>>t;
    nowt+=x-nowp;
    int A=nowt%(2*t);
    if(t-A>=w)nowt+=w;
    else nowt+=2*t-A+w;
    nowp=x+w;
  }
  nowt+=l-nowp;
  cout<<nowt<<endl;
}