package main

import (
	"fmt"
)

func main() {
	var N, L, t, pos int
	fmt.Scan(&N, &L)
	for i := 0; i < N; i++ {
		var X, W, T int
		fmt.Scan(&X, &W, &T)
		t += X - pos
		pos = X
		rem := t % (T * 2)
		if rem+W > T {
			t = (t/(T*2)+1)*(T*2) + W
		} else {
			t += W
		}
		pos += W
	}
	fmt.Println(t + L - pos)
}