Submission #643886

#	Time	Username	Problem	Language	Result	Execution time	Memory
643886		ghostwriter	Divide and conquer (IZhO14_divide)	C++14	100 / 100	60 ms	7120 KiB

divide

#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
#include <debug.h>
#endif
#define ft front
#define bk back
#define st first
#define nd second
#define ins insert
#define ers erase
#define pb push_back
#define pf push_front
#define _pb pop_back
#define _pf pop_front
#define lb lower_bound
#define ub upper_bound
#define mtp make_tuple
#define bg begin
#define ed end
#define all(x) (x).bg(), (x).ed()
#define sz(x) (int)(x).size()
typedef long long ll; typedef unsigned long long ull;
typedef double db; typedef long double ldb;
typedef pair<int, int> pi; typedef pair<ll, ll> pll;
typedef vector<int> vi; typedef vector<ll> vll; typedef vector<pi> vpi; typedef vector<pll> vpll;
typedef string str;
template<typename T> T gcd(T a, T b) { return (b == 0? a : gcd(b, a % b)); }
template<typename T> T lcm(T a, T b) { return a / gcd(a, b) * b; }
#define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
#define FOS(i, r, l) for (int (i) = (r); (i) >= (l); --(i))
#define EACH(i, x) for (auto &(i) : (x))
#define WHILE while
#define file "TEST"
mt19937 rd(chrono::steady_clock::now().time_since_epoch().count());
ll rand(ll l, ll r) { return uniform_int_distribution<ll>(l, r)(rd); }
/*
    Tran The Bao
    VOI23 gold medal
*/
const ll oo = 1e18;
const int N = 1e5 + 5;
const int Nx2 = 2e5 + 5;
int n, x[N], g[N], d[N];
ll f[N], s[N], f1[Nx2], rs = -oo;
vll v;
int getpos(ll x) { return lb(all(v), x) - v.bg(); }
void upd(int pos, ll v) { for (int i = pos; i >= 1; i -= (i & -i)) f1[i] = min(f1[i], v); }
ll get(int pos) { ll rs = oo; for (int i = pos; i < sz(v); i += (i & -i)) rs = min(rs, f1[i]); return rs; }
signed main() {
    ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    // freopen(file".inp", "r", stdin);
    // freopen(file".out", "w", stdout);
    cin >> n;
    FOR(i, 1, n) cin >> x[i] >> g[i] >> d[i];
    FOR(i, 1, n) {
    	f[i] = f[i - 1] + d[i];
    	s[i] = s[i - 1] + g[i];
    	v.pb(-f[i] + x[i]);
    	v.pb(-f[i - 1] + x[i]);
    }
    v.pb(-oo);
    sort(all(v));
    FOR(i, 1, sz(v) - 1) f1[i] = oo;
    FOR(i, 1, n) {
    	int pos = getpos(-f[i - 1] + x[i]);
    	upd(pos, s[i - 1]);
    	pos = getpos(-f[i] + x[i]);
    	rs = max(rs, s[i] - get(pos));
    }
    cout << rs;
    return 0;
}
/*
2
0 4 1
3 5 1
*/
/*
From Benq:
    stuff you should look for
        * int overflow, array bounds
        * special cases (n=1?)
        * do smth instead of nothing and stay organized
        * WRITE STUFF DOWN
        * DON'T GET STUCK ON ONE APPROACH
*/

Compilation message (stderr)

divide.cpp: In function 'int main()':
divide.cpp:30:31: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
   30 | #define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
      |                               ^
divide.cpp:55:5: note: in expansion of macro 'FOR'
   55 |     FOR(i, 1, n) cin >> x[i] >> g[i] >> d[i];
      |     ^~~
divide.cpp:30:31: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
   30 | #define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
      |                               ^
divide.cpp:56:5: note: in expansion of macro 'FOR'
   56 |     FOR(i, 1, n) {
      |     ^~~
divide.cpp:30:31: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
   30 | #define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
      |                               ^
divide.cpp:64:5: note: in expansion of macro 'FOR'
   64 |     FOR(i, 1, sz(v) - 1) f1[i] = oo;
      |     ^~~
divide.cpp:30:31: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
   30 | #define FOR(i, l, r) for (int (i) = (l); (i) <= (r); ++(i))
      |                               ^
divide.cpp:65:5: note: in expansion of macro 'FOR'
   65 |     FOR(i, 1, n) {
      |     ^~~

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