1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
#include <bits/stdc++.h>
using namespace std;

int main() {
    cin.tie(0)->sync_with_stdio(0);

    long long n, c;
    cin >> n >> c;
    vector<pair<long long, long long>> b(n);

    for (auto &i : b) cin >> i.first >> i.second;

    const long long INF = -1e18;
    vector<long long> bp(500001, INF);

    long long ga = INF, res = 0;

    long long i = 0;
    while (i < n) {

        long long a = b[i].first;
        vector<pair<long long, long long>> g;
        //cout << j << '\n' << i << "chuj" <<'\n';
        long long j = i;

        while (j < n and b[j].first == a) {
            long long w = b[j].second;
            long long cnd = max({0LL, bp[w], ga - c});
            long long dp = a + cnd;
            g.emplace_back(w, dp);
            res = max(res, dp);
            j++;
        }

        for (auto &[w, dp] : g) {
            bp[w] = max(bp[w], dp);
            ga = max(ga, dp);
        }

        i = j;
    }

    cout << res;
}