#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define int ll
constexpr int INF = 1ull << 60;
int w[100000 + 5];
int N, K;
signed main() {
ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);
cin >> N >> K;
for (int i = 0; i < N - 1; ++i) cin >> w[i] >> w[i] >> w[i];
int cnt = 0;
for (int i = 0; i < N - 1; ++i) {
int len = 0;
int maxw = -1;
for (int j = i; j < N - 1; ++j) {
len++;
maxw = max(maxw, w[j]);
if (maxw - len >= K) cnt += 2;
// cout << i << ' ' << j << ' ' << len << ' ' << maxw << endl;
}
}
cout << cnt;
}
