#include using namespace std; typedef long long ll; const ll MOD = 1e9 + 7; int main(){ int N, L; cin >> N >> L; int tm = 0; int x = 0; for(int i=0;i> X >> W >> T; tm += X - x; if((tm / T) % 2 == 1){ tm += T - tm % T; } else { int rem = T - tm % T; if(W > rem){ tm += rem; tm += T; } } tm += W; x = X + W; } tm += L - x; cout << tm << endl; return 0; }