Submission #564863

#	Time	Username	Problem	Language	Result	Execution time	Memory
564863		Sam_a17	Divide and conquer (IZhO14_divide)	C++14	100 / 100	132 ms	14068 KiB

divide

#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
// #include "temp.cpp"
#include <cstdio>
using namespace std;
 
#ifndef ONLINE_JUDGE
#define dbg(x) cerr << #x <<" "; print(x); cerr << endl;
#else
#define dbg(x)
#endif
 
#define sz(x) (int((x).size()))
#define len(x) (int)x.length()
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define clr(x) x.clear()
#define uniq(x) x.resize(unique(all(x)) - x.begin());
#define blt __builtin_popcount
 
#define pb push_back
#define pf push_front
#define popf pop_front
#define popb pop_back
 
void print(long long t) {cerr << t;}
void print(int t) {cerr << t;}
void print(string t) {cerr << t;}
void print(char t) {cerr << t;}
void print(double t) {cerr << t;}
void print(long double t) {cerr << t;}
void print(unsigned long long t) {cerr << t;}
 
template <class T> void print(set <T> v);
template <class T> void print(vector <T> v);
template <class T> void print(multiset <T> v);
template <class T, class V> void print(map <T, V> v);
template <class T, class V> void print(pair <T, V> p);
template <class T, class V> void print(T v[],V n) {cerr << "["; for(int i = 0; i < n; i++) {print(v[i]); cerr << " "; } cerr << "]";}
template <class T, class V> void print(pair <T, V> p) {cerr << "{"; print(p.first); cerr << ","; print(p.second); cerr << "}";}
template <class T> void print(vector <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(deque<T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(set <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(multiset <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T, class V> void print(map <T, V> v) {cerr << "[ "; for (auto i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T, class V> void print(unordered_map<T, V> v) {cerr << "[ "; for (auto i : v) {print(i); cerr << " ";} cerr << "]";}
 
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
#define nl '\n'
 
// for grid problems
int dx[8] = {-1,0,1,0,1,-1,1,-1};
int dy[8] = {0,1,0,-1,1,1,-1,-1};
 
// lowest / (1 << 17) >= 1e5 / (1 << 18) >= 2e5 / (1 << 21) >= 1e6
void fastIO() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr); cout.tie(nullptr);
}
 
// file in/out
void setIO(string str = "") {
  fastIO();
 
  if (str != "" && str != "input") {
    freopen((str + ".in").c_str(), "r", stdin);
    freopen((str + ".out").c_str(), "w", stdout);
  }
 
  if(str == "input") {
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
  }
}
// Indexed Set
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
const long long inf = 1e8;
int n;
 
struct Node {
  long long x, g, d;
};
 
struct segTree {
  struct node {
    long long value, lazy, maxi;
  };
  int size = 1;
  vector<node> tree;
 
  node combine(node a, node b) {
    node c;
    c.value = a.value + b.value;
    c.maxi = max(a.maxi, b.maxi);
    c.lazy = 0;
    return c;
  }
 
  void init(int s) {
    while(s > size) {
      size *= 2;
    }
    tree.assign(2 * size - 1, {0, 0, -inf});
  }
 
  void propagate(int x, int lx, int rx) {
    if(rx - lx == 1 || !tree[x].lazy) {
      tree[x].lazy = 0LL;
      return;
    }
 
    int mid = (lx + rx) / 2;
 
    tree[2 * x + 1].value += (mid - lx) * tree[x].lazy;
    tree[2 * x + 1].lazy += tree[x].lazy;
    tree[2 * x + 1].maxi += tree[x].lazy;
 
    tree[2 * x + 2].value += (rx - mid) * tree[x].lazy;
    tree[2 * x + 2].lazy += tree[x].lazy;
    tree[2 * x + 2].maxi += tree[x].lazy;
 
    tree[x].lazy = 0LL;
//    propagate(2 * x + 1, lx, mid);
//    propagate(2 * x + 2, mid, rx);
  }
 
  void upd(int l, int r, long long value, int x, int lx, int rx) {
    propagate(x, lx, rx);
    if(lx >= r || rx <= l) {
      return;
    }
 
    if(lx >= l && rx <= r) {
      tree[x].value += (rx - lx) * value;
      tree[x].maxi += value;
      tree[x].lazy = value;
      propagate(x, lx, rx);
      return;
    }
 
    int mid = (lx + rx) / 2;
    upd(l, r, value, 2 * x + 1, lx, mid);
    upd(l, r, value, 2 * x + 2, mid, rx);
    tree[x] = combine(tree[2 * x + 1], tree[2 * x + 2]);
  }
 
  void upd(int l, int r, long long value) {
    upd(l, r, value, 0, 0, size);
  }
 
  int find(int x, int lx, int rx) {
    propagate(x, lx, rx);
    if(rx - lx == 1) {
      return lx;
    }
 
    int mid = (lx + rx) / 2;
    if(tree[2 * x + 2].maxi >= 0) {
      return find(2 * x + 2, mid, rx);
    } else {
      return find(2 * x + 1, lx, mid);
    }
  }
 
  int find() {
    propagate(0, 0, size);
    if(tree[0].maxi < 0) {
      return -1;
    }
    return find(0, 0, size);
  }
 
};
 
segTree seg;
 
void solve_() {
  cin >> n, seg.init(n + 1);
  vector<Node> a(n + 1), prefix(n + 1);
  for(int i = 1; i <= n; i++) {
    cin >> a[i].x >> a[i].g >> a[i].d;
  }
 
  for(int i = 1; i <= n; i++) {
    prefix[i].g = prefix[i - 1].g + a[i].g;
    prefix[i].d = prefix[i - 1].d + a[i].d;
//    dbg(prefix[i].d - (a[i].x - a[1].x))
    seg.upd(i, i + 1, inf + prefix[i].d - (a[i].x - a[1].x));
  }
 
  long long answ = 0;
  for(int i = 1; i <= n; i++) {
    if(i >= 2) {
//      dbg((a[i].x - a[i - 1].x) - a[i - 1].d)
      seg.upd(i, n + 1, (a[i].x - a[i - 1].x) - a[i - 1].d);
    }
 
    int curr = seg.find();
 
    if(curr >= i) {
      answ = max(answ, prefix[curr].g - prefix[i - 1].g);
    }
  }
 
  printf("%lld\n", answ);
}
 
int main() {
  setIO("");
 
 
  auto solve = [&](int test_case)-> void {
    while(test_case--) {
      solve_();
    }
  };
 
  int test_cases = 1;
  solve(test_cases);
 
  return 0;
} 

Compilation message (stderr)

divide.cpp: In function 'void setIO(std::string)':
divide.cpp:67:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   67 |     freopen((str + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
divide.cpp:68:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   68 |     freopen((str + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
divide.cpp:72:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   72 |     freopen("input.txt", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
divide.cpp:73:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   73 |     freopen("output.txt", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

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