Submission #407374

#	Time	Username	Problem	Language	Result	Execution time	Memory
407374		AugustinasJucas	Salesman (IOI09_salesman)	C++14	60 / 100	1809 ms	65536 KiB

salesman

#include <bits/stdc++.h>
using namespace std;
const long long inf = 1e18;
struct medis{
	struct node{
		long long val = -inf;
		int l, r;
	};
	vector<node> mas;
	int n;
	int dbInd = 0;
	void build(int v){
		if(v >= n){
			mas[v].l = mas[v].r = dbInd++;
		}else{
			build(v*2); build(v*2+1);
			mas[v].l = mas[v*2].l;
			mas[v].r = mas[v*2+1].r;
		}
	}
	medis(int dd){
		n = dd;
		mas.resize(2 * n + 1);
		build(1);
	}
	void change(int v, int l, int r, long long x){
		if(l <= mas[v].l && mas[v].r <= r){
			mas[v].val = x;
		}else if(r < mas[v].l || mas[v].r < l){
			return;
		}else{
			change(v*2, l, r, x);
			change(v*2+1, l, r, x);
			mas[v].val = max(mas[v*2].val, mas[v*2+1].val);
		}
	}
	pair<long long, int> get(int v, int l, int r){
		if(l <= mas[v].l && mas[v].r <= r){
			return {mas[v].val, mas[v].l};
		}else if(r < mas[v].l || mas[v].r < l){
			return {-inf, -inf};
		}else{
			return max(get(v*2, l, r), get(v*2+1, l, r));
		}
	}
};

int n, U, D, s;
const int dydis = 5e5 + 10;
vector<pair<int, int> > fairs[dydis];
long long curAns[dydis];
medis v1(dydis), v2(dydis);
void updateCur(int ind, long long x){
	curAns[ind] = x;
	//[curAns[y]+u*y]
	//cout << ind << " -> " << x << endl;
	v1.change(1, ind, ind, curAns[ind] + 1ll * U * ind);
	v2.change(1, ind, ind, curAns[ind] - 1ll * D * ind);
}	
pair<long long, int> fMx1(int l, int r){
	//cout << l << "; " << r << " maximumas, pirmame: " << v1.get(1, l, r) << endl;
	return v1.get(1, l, r);
}
pair<long long, int> fMx2(int l, int r){
	return v2.get(1, l, r);
}
void daryk(int d){
	if(fairs[d].size() == 0) return;
	int kurMax = -1;
	int lastFair = -1;
	long long pref = 0;
	vector<pair<int, long long> > chang;
	//cout << "darom " << d << "-aja diena!" << endl;
	for(auto x : fairs[d]){
		long long bv = (kurMax == -1 ? -inf : 1ll * curAns[kurMax] - 1ll * (x.first - kurMax) * U + pref); 
		long long galiBut = fMx1(lastFair+1, x.first-1).first - 1ll * x.first * U; 
		// y(ind) is [last+1;  x.first-1],
		// kad A = curAns[y]-(x.first-y) * u butu didziausias ir A > bv
		// A = [curAns[y]+u*y] - [x.first*u]
		//      ^^^^^^^^^^^^^ rasti sita max intervale y [last+1; x.first-1]
		//cout << "bv = " << bv << ", galiButi = " << galiBut <<", pl = " << x.second << endl;
		
		chang.push_back({x.first, max(bv, galiBut) + x.second});
		if(galiBut > bv){
			kurMax = fMx1(lastFair+1, x.first-1).second;
			pref = 0;
		}
		pref += x.second;
		lastFair = x.first;
	}
	lastFair = dydis-1;
	kurMax = dydis-1;
	pref = 0;
	for(int i = (int)fairs[d].size()-1; i > -1; i--){
		auto x = fairs[d][i];
		long long bv = (kurMax == dydis-1 ? -inf : 1ll * curAns[kurMax] - 1ll * (kurMax - x.first) * D + pref);
		long long galiBut = fMx2(x.first+1, lastFair-1).first + 1ll * x.first * D;
	//	cout << "FMX2 = " << fMx2(x.first+1, lastFair-1) <<", dar pridesiu " << x.first * D << ", xf = " << x.first << ", d = " << D<<endl;
	//	cout << "bv = " << bv << ", galiButi = " << galiBut <<", pl = " << x.second << endl;
		// y(ind) is [x.first+1;  x.last-1],
		// kad A = curAns[y]-(y-x.first) * d butu didziausias ir A > bv
		// A = [curAns[y]-d*y] + [x.first*u]
		chang.push_back({x.first, max(bv, galiBut) + x.second});
		if(galiBut > bv){
			kurMax = fMx2(x.first+1, lastFair-1).second;
			pref = 0;
		}
		pref += x.second;
		lastFair = x.first;
	}
	for(auto x : chang){
		int ind = x.first;
		long long val = x.second;
	//	cout << "norim " << ind << " pakeisti i " << val << endl;
		if(val < curAns[ind]){
			continue;
		}
		updateCur(ind, val);
	}
}
int main(){
	cin.tie(NULL);
	ios_base::sync_with_stdio(false);
	for(int i = 0; i < dydis; i++) curAns[i] = -inf;
	cin >> n >> D >> U >> s;
	
	updateCur(s, 0);
	for(int i = 0; i < n; i++){
		int t, l, p; cin >> t >> l >> p;
		fairs[t].push_back({l, p});
	}
	for(int i = 0; i < dydis; i++){
		sort(fairs[i].begin(), fairs[i].end());
	}
	for(int i = 0; i < dydis; i++){
		daryk(i);
	}
	long long ans = 0;
	for(int i = 0; i < dydis; i++){
		ans = max(ans, curAns[i] - 1ll * (s > i ? U : D) * abs(s-i));
	}
	cout << ans;
	return 0;
}

• Subtask 1: 60 / 100