Submission #404244

#	Time	Username	Problem	Language	Result	Execution time	Memory
404244		VROOM_VARUN	Strange Device (APIO19_strange_device)	C++17	100 / 100	614 ms	35308 KiB

strange_device

/*
ID: varunra2
LANG: C++
TASK: device
*/

#include <bits/stdc++.h>
using namespace std;

#ifdef DEBUG
#include "lib/debug.h"
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#define debug_arr(...) \
  cerr << "[" << #__VA_ARGS__ << "]:", debug_arr(__VA_ARGS__)
#pragma GCC diagnostic ignored "-Wsign-compare"
//#pragma GCC diagnostic ignored "-Wunused-parameter"
//#pragma GCC diagnostic ignored "-Wunused-variable"
#else
#define debug(...) 42
#endif

#define int long long

#define EPS 1e-9
#define IN(A, B, C) assert(B <= A && A <= C)
#define INF (int)1e9
#define MEM(a, b) memset(a, (b), sizeof(a))
#define MOD 1000000007
#define MP make_pair
#define PB push_back
#define all(cont) cont.begin(), cont.end()
#define rall(cont) cont.end(), cont.begin()
#define x first
#define y second

const double PI = acos(-1.0);
typedef long long ll;
typedef long double ld;
typedef pair<int, int> PII;
typedef map<int, int> MPII;
typedef multiset<int> MSETI;
typedef set<int> SETI;
typedef set<string> SETS;
typedef vector<int> VI;
typedef vector<PII> VII;
typedef vector<VI> VVI;
typedef vector<string> VS;

#define rep(i, a, b) for (int i = a; i < (b); ++i)
#define trav(a, x) for (auto& a : x)
#define sz(x) (int)(x).size()
typedef pair<int, int> pii;
typedef vector<int> vi;
#pragma GCC diagnostic ignored "-Wsign-compare"
// util functions

int32_t main() {
  // #ifndef ONLINE_JUDGE
  // freopen("device.in", "r", stdin);
  // freopen("device.out", "w", stdout);
  // #endif
  cin.sync_with_stdio(0);
  cin.tie(0);

  int n, a, b;
  cin >> n >> a >> b;

  int gc = __gcd(a, b + 1);

  // t = b * x
  // b*x + x = (b + 1)*x == 0 mod a

  int x = a / gc;

  int mx;

  if ((int)2e18 / x < b) {
    mx = (int)2e18;
  } else
    mx = x * b;

  VII vals;

  for (int i = 0; i < n; i++) {
    int x, y;
    cin >> x >> y;
    vals.PB(MP(x, y));
  }

  for (int i = 0; i < n; i++) {
    int to = (vals[i].x / mx + 1) * mx - 1;
    if (vals[i].y <= to) {
      vals[i].x %= mx;
      vals[i].y %= mx;
      continue;
    } else {
      vals.PB({0, vals[i].y % mx});
      vals[i].y = to;
      vals[i].y %= mx;
      vals[i].x %= mx;
    }
    // vals[i].y = min(vals[i].y, (vals[i].x / mx + 1) * mx - 1);
    // vals[i].x %= mx;
    // vals[i].y %= mx;
  }

  int ret = 0;

  sort(all(vals));

  int mxx = -1;

  for (int i = 0; i < sz(vals); i++) {
    // from mxx -> vals[i].y - mxx -> vals[i].x
    ret += vals[i].y - vals[i].x + 1;
    ret -= min(vals[i].y - vals[i].x + 1, max(0ll, mxx - vals[i].x + 1));
    mxx = max(mxx, vals[i].y);
  }

  cout << ret << '\n';

  return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 5 / 5
• Subtask 3: 5 / 5
• Subtask 4: 5 / 5
• Subtask 5: 5 / 5
• Subtask 6: 20 / 20
• Subtask 7: 20 / 20
• Subtask 8: 30 / 30