кефа и компания

#include <iostream>

using namespace std;

struct Pair {
    int m, h;
} a[100500];

bool cmp(Pair p1, Pair p2) {
    return p1.m < p2.m;
}

int main() {

    cin >> n >> d;

    for (int i = 1; i <= n; i++)
        cin >> a[i].m >> a[i].h;

    sort(a + 1, a + n + 1, cmp);

    for (int i = 1; i <= n; i++)
        d[i] = d[i - 1] + a[i].h;

    for (int i = 1; i <= n; i++) {
        l = i;
        r = n;
        pos = -1;
        while(l <= r) {
            int mid = (l + r) / 2;
            if (a[mid].m - a[i].m < d) {
                pos = mid;
                l = mid + 1;
            }
            else
                r = mid - 1;
        }
        if (pos == -1)
            ans = max(ans, a[i].h);
        else
            ans = max(ans, d[pos] - d[i - 1]);
    }

    cout << ans;

    return 0;

}