Submission #733422

#	Time	Username	Problem	Language	Result	Execution time	Memory
733422		penguin133	Salesman (IOI09_salesman)	C++17	6 / 100	169 ms	65536 KiB

salesman

#include <bits/stdc++.h>
using namespace std;

//#define int long long
#define pi pair<int, int>
#define pii pair<int, pi>
#define fi first
#define se second
#ifdef _WIN32
#define getchar_unlocked _getchar_nolock
#endif
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
int n, u, d, s;
int dp[500005];
pii A[500005];

struct node{
	int s, e, m, val;
	node *l, *r;
	node(int _s, int _e){
		s = _s, e = _e, m = (s + e) >> 1, val = -1e18;
		if(s != e)l = new node(s, m), r = new node(m+1, e);
	}
	void upd(int p, int v){
		if(s == e)val = max(val, v);
		else{
			if(p <= m)l->upd(p, v);
			else r->upd(p, v);
			val = max(l->val, r->val);
		}
	}
	int qry(int a, int b){
		if(s == a && b == e)return val;
		else if(b <= m)return l->qry(a, b);
		else if(a > m)return r->qry(a, b);
		else return max(l->qry(a, m), r->qry(m+1, b));
	}
}*dwn, *up;

void solve(){
	cin >> n >> u >> d >> s;
	int mx = s;
	for(int i=1;i<=n;i++){
		cin >> A[i].fi >> A[i].se.fi >> A[i].se.se;
		mx = max(mx, A[i].se.fi);
	}
	dwn = new node(1, mx);
	up = new node(1, mx);
	sort(A+1, A+n+1);
	A[0].se.fi = s;
	A[n+1].se.fi = s;
	dwn->upd(s, -d * s);
	up->upd(s, u * s);
	for(int i=1;i<=n+1;i++){
		int top = dwn->qry(A[i].se.fi, mx) + d * A[i].se.fi + A[i].se.se;
		int bot = up->qry(1, A[i].se.fi) - u * A[i].se.fi + A[i].se.se;
		dp[i] = max(top, bot);
		/*
		for(int j=i-1;j>=0;j--){
			int cst;
			if(A[j].se.fi > A[i].se.fi)cst = d * (A[j].se.fi - A[i].se.fi);
			else cst = u * (A[i].se.fi - A[j].se.fi);
			dp[i] = max(dp[i], dp[j] - cst + A[i].se.se);
		}
		*/
		dwn->upd(A[i].se.fi, dp[i] - d * A[i].se.fi);
		up->upd(A[i].se.fi, dp[i] + u * A[i].se.fi);
	}
	cout << dp[n+1];
}

main(){
	ios::sync_with_stdio(0);cin.tie(0);
	int tc = 1;
	//cin >> tc;
	for(int tc1=1;tc1<=tc;tc1++){
		// cout << "Case #" << tc1 << ": ";
		solve();
	}
}

Compilation message (stderr)

salesman.cpp: In constructor 'node::node(int, int)':
salesman.cpp:21:43: warning: overflow in conversion from 'double' to 'int' changes value from '-1.0e+18' to '-2147483648' [-Woverflow]
   21 |   s = _s, e = _e, m = (s + e) >> 1, val = -1e18;
      |                                           ^~~~~
salesman.cpp: At global scope:
salesman.cpp:72:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   72 | main(){
      | ^~~~

• Subtask 1: 6 / 100