Submission #782439

#	Time	Username	Problem	Language	Result	Execution time	Memory
782439		kebine	Strange Device (APIO19_strange_device)	C++17	100 / 100	387 ms	18932 KiB

strange_device

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll, ll> pll;
const ll MAX = 1e18;

vector<pll> vec;
// {Left, Right}
ll n, a, b, length, ans = 0;

void opr(ll l, ll r) {
  ll pushl = min(l, r);
  ll pushr = max(l, r);

  if (pushl == 0) {
    // pushl = length;
  }

  if (pushr == 0) {
    // pushr = length;
  }

  vec.push_back({pushl, pushr});
}

void answer() {
  sort(vec.begin(), vec.end());

  ll idx = -1;
  for (int i = 0; i < vec.size(); ++i)
  {
    // cout << vec[i].first << " " << vec[i].second << "\n";
    pll now = vec[i];
    if (now.second < now.first)
    {
      continue ;
    }

    if (idx >= now.first)
    {
      if (now.second <= idx)
      {
        continue ;
      } else {
        idx++;
        ans += now.second - idx + 1;
        idx = now.second;
      }
    } else {
      idx = now.first;
      ans += now.second - idx + 1;
      idx = now.second;
    }
  }

  cout << ans << "\n";
}

ll fpb(ll a, ll b) {
  if (a == 0)
  {
    return b;
  }

  return fpb(b%a, a);
}

int main(){
  ios_base::sync_with_stdio(false); cin.tie(0);
  cin >> n >> a >> b;
  ull lebek;
  // if (a == 1) {
  //   lebek = b;
  // } else {
  //   if (a % 2)
  //   {
  //     lebek = a * b;
  //   } else {
  //     lebek = (a/2) * b;
  //   }
  // }

  lebek = a / fpb(a, b+1) * b;

  // length = lebek;
  length = min(lebek, (ull)MAX);


  for (int i = 0; i < n; ++i)
  {
    ll nowl, nowr;
    cin >> nowl >> nowr;

    if (nowr-nowl+1 >= length)
    {
      cout << length << "\n";
      return 0;
    }

    if (nowl/length != nowr/length) {
      opr(nowl % length + 1, length);
      opr(1, nowr % length + 1);
    } else {
      opr(nowl % length + 1, nowr % length + 1);
    }
  }

  answer();
  return 0;
}

Compilation message (stderr)

strange_device.cpp: In function 'void answer()':
strange_device.cpp:31:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   31 |   for (int i = 0; i < vec.size(); ++i)
      |                   ~~^~~~~~~~~~~~

• 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