kickstartroundh-solution3.cpp

#include <cmath>
#include <functional>
#include <fstream>
#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <set>
#include <map>
#include <list>
#include <time.h>
#include <math.h>
#include <random>
#include <deque>
#include <queue>
#include <cassert>
#include <unordered_map>
#include <unordered_set>
#include <iomanip>
#include <bitset>
#include <sstream>
#include <chrono>
#include <cstring>

using namespace std;

typedef long long ll;

#ifdef iq
  mt19937 rnd(228);
#else
  mt19937 rnd(chrono::high_resolution_clock::now().time_since_epoch().count());
#endif

int main() {
#ifdef iq
  freopen("a.in", "r", stdin);
#endif
  ios::sync_with_stdio(0);
  cin.tie(0);
  int t;
  cin >> t;
  auto solve = [&] () {
    int n, k;
    cin >> n >> k;
    vector <pair <int, int> > e;
    for (int i = 0; i < n; i++) {
      int l, r;
      cin >> l >> r;
      e.push_back({l, r});
    }
    sort(e.begin(), e.end());
    int last = 0;
    int ans = 0;
    for (int i = 0; i < n; i++) {
      e[i].first = max(e[i].first, last);
      if (e[i].first < e[i].second) {
        int ret = (e[i].second - e[i].first + k - 1) / k;
        ans += ret;
        last = e[i].first + ret * k;
      }
    }
    cout << ans;
  };
  for (int tc = 1; tc <= t; tc++) {
    cout << "Case #" << tc << ": ";
    solve();
    cout << '\n';
  }
}