제출 #642236

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
642236		andecaandeci	Lasers (NOI19_lasers)	C++17	10 / 100	67 ms	684 KiB

lasers

#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("Ofast")
typedef long long ll;
// const ll mod = 1e9 + 7;
const ll MAXN = 1e6 + 5;
#define vi vector<int>
#define vll vector<ll>
#define pii pair<int, int>
#define pll pair<ll, ll>
#define mp make_pair
#define pb push_back
#define lb lower_bound
#define ub upper_bound
#define fi first
#define sc second
#define endl '\n'
#define gl                        ios_base::sync_with_stdio(0);   cin.tie(0);                     cout.tie(0)

int main()
{
  gl;

  int l, r;
  cin >> l >> r;

  if (r == 1)
  {
    int x, a;
    cin >> x >> a;
    cout << max(0, 2 * a - l) << endl;
    return 0;
  }

  int L = 1e9, R = 0;

  for (int i = 0; i < r; i++)
  {
    int x, a;
    cin >> x >> a;
    if (a <= l / 2)
      continue;
    L = min(L, l - a + 1);
    R = max(R, a);
  }

  cout << R - L + 1 << endl;

  return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 0 / 14
• Subtask 3: 0 / 20
• Subtask 4: 0 / 21
• Subtask 5: 0 / 22
• Subtask 6: 0 / 13