Submission #392237

#	Time	Username	Problem	Language	Result	Execution time	Memory
392237		acm	Divide and conquer (IZhO14_divide)	C++14	100 / 100	54 ms	7512 KiB

divide

#include <bits/stdc++.h>
#define speed                   \
  ios_base::sync_with_stdio(0); \
  cin.tie(0);                   \
  cout.tie(0);
#define precision     \
  cout.precision(30); \
  cerr.precision(10);
#define ll long long
#define ld long double
#define pll pair<ll, ll>
#define pii pair<int, int>
#define forn(n) for (int i = 1; i <= n; i++)
#define forlr(l, r) for (int i = l; i != r; (l > r ? i-- : i++))
#define pb(x) push_back(x)
#define sz(x) (int)x.size()
#define mp(x, y) make_pair(x, y)
#define all(x) x.begin(), x.end()
#define pc(x) __builtin_popcount(x)
#define pcll(x) __builtin_popcountll(x)
#define F first
#define S second
using namespace std;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
void ioi(string name) {
  freopen((name + ".in").c_str(), "r", stdin);
  freopen((name + ".out").c_str(), "w", stdout);
}
ll n, k, m = -(1LL << 60), t = -(1LL << 60), g[100005], e[100005], f[200005];
pair<ll, pair<ll, ll>> a[100005];
vector<ll> b;
int main() {
  speed;
  precision;
  // code
  cin >> n;
  for (int i = 1; i <= n; i++) {
    ll x, y, z;
    cin >> x >> y >> z;
    a[i] = mp(x, mp(y, z));
    g[i] = g[i - 1] + y;
    e[i] = e[i - 1] + z;
    b.pb(a[i].F - e[i - 1]);
    b.pb(a[i].F - e[i]);
  }
  sort(all(b));
  b.erase(unique(all(b)), b.end());
  for (int i = 1; i <= n; i++) {
    f[lower_bound(all(b), a[i].F - e[i]) - b.begin() + 1] = g[i];
  }
  for (int i = 1; i <= n; i++) {
    ll c = lower_bound(all(b), a[i].F - e[i - 1]) - b.begin() + 1;
    for (; k <= c; k++) t = max(t, f[k]);
    m = max(m, t - g[i - 1]);
  }
  cout << m;
  // endl
#ifndef ONLINE_JUDGE
  cerr << "\nTime elapsed: " << 1.0 * clock() / CLOCKS_PER_SEC << " s.\n";
#endif
  return 0;
}

Compilation message (stderr)

divide.cpp: In function 'void ioi(std::string)':
divide.cpp:26:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   26 |   freopen((name + ".in").c_str(), "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
divide.cpp:27:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   27 |   freopen((name + ".out").c_str(), "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 17 / 17
• Subtask 2: 31 / 31
• Subtask 3: 52 / 52