Submission #1130396

#	Time	Username	Problem	Language	Result	Execution time	Memory
1130396		zhasyn	Divide and conquer (IZhO14_divide)	C++20	100 / 100	103 ms	4240 KiB

divide

#include <bits/stdc++.h>
#define pb push_back
#define pf push_front
using namespace std;
#define F first
#define S second
typedef long long ll;
#define pii pair <int, int>
#define pll pair <ll, ll>
typedef long double ld;
const ll N = 1e5 + 100, M = 500 + 10, len = 315, inf = 1e18;
const ll mod = 998244353;
ll um(ll a, ll b){
	return (1LL * a * b) % mod;
}
ll subr(ll a, ll b){
	return ((1LL * a - b) % mod + mod) % mod;
}
ll bp(ll x, ll step){
	ll res = 1;
	while(step){
		if(step & 1) res = um(res, x);
		x = um(x, x);
		step /= 2;
	}
	return res;
}
ll inv(ll x){
	return bp(x, mod - 2);
}
ll p[N], g[N], e[N], mx;
void calc(ll l, ll r){
	if(r - l == 0) return;
	if(r - l == 1){
		mx = max(mx, g[l]);
		return;
	}
	ll mid = (r + l) / 2;
	calc(l, mid);
	calc(mid, r);
	vector <pll> st;
	ll dis, gold = 0, en = 0;
	for(ll i = mid - 1; i >= l; i--){
		dis = p[mid] - p[i];
		gold += g[i];
		en += e[i];
		while((ll)st.size() != 0){
			pll v = st.back();
			if(dis - en <= v.S) st.pop_back();
			else break;
		}
		st.pb({gold, dis - en});
	}
	// cout << l << " "<< r << " Here\n";
	// for(auto u : st){
		// cout << u.F << " "<< u.S << endl;
	// }
	// cout << endl;
	en = gold = 0;
	for(ll i = mid; i < r; i++){
		dis = p[i] - p[mid];
		en += e[i];
		gold += g[i];
		
		ll lx = 0, rx = (ll)st.size();
		while(rx - lx > 1){
			ll midx = (lx + rx) / 2;
			if(st[midx].S <= en - dis) lx = midx;
			else rx = midx;
		}
		if(en - dis >= st[lx].S){
			mx = max(mx, st[lx].F + gold);
		}
	}
}
int main() {
	//ios_base::sync_with_stdio(false);
	//cin.tie(nullptr);
	//cout.tie(nullptr);
	ll n;
	cin >> n;
	for(ll i = 0; i < n; i++){
		cin >> p[i] >> g[i] >> e[i];
	}
	calc(0, n);
	cout << mx;
  return 0;
}

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