E (ODS)

#include <bits/stdc++.h>

using namespace std;

const int N = 1e5;
const long long inf = 2e18;

int n;
long long T, d[N];

int main(){
    cin >> n >> T;

    vector < pair <int, long long> > vec;
    for (int i = 1; i <= n; i++) {
        long long p, v;
        cin >> p >> v;
        vec.push_back(make_pair(p, p + v * T));
    }

    d[0] = -inf;
    for (int i = 1; i < N; i++) {
        d[i] = inf;
    }

    sort(vec.rbegin(), vec.rend());

    for (int i = 0; i < vec.size(); i++) {
        long long finish = vec[i].second + i;
        int j = upper_bound(d, d + n, finish) - d;
        if (d[j - 1] < finish && d[j] > finish) {
            d[j] = finish;
        }
    }

    for (int i = N - 1; i >= 0; i--) {
        if (d[i] != inf) {
            cout << i << endl;
            return 0;
        }
    }
}