제출 #977531

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
977531		Halym2007	여행하는 상인 (APIO17_merchant)	C++17	100 / 100	103 ms	1624 KiB

merchant

/*
Kotda etyan zatlarym shu comment-da dusindiryar : https://codeforces.com/blog/entry/51981?#comment-360508
Solution of my code is explained in this comment : https://codeforces.com/blog/entry/51981?#comment-360508
*/
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
#define ff first
#define ss second
#define sz size()
const int N = 1e2 + 5;
const int K = 1e3 + 5;

int buy[N][K], sell[N][K], n, m, d;
ll val[N][N], dis[N][N], profit[N][N];

ll INF = 1e13;
 
bool check (int x) {
	// jog - x * time >= 0
	for (int i = 1; i <= n; ++i) {
		for (int j = 1; j <= n; ++j) {
			if (dis[i][j] != INF) {
				val[i][j] = profit[i][j] - x * dis[i][j];
			}
			else val[i][j] = -INF;
		}
		val[i][i] = -INF;
	}
	for (int k = 1; k <= n; ++k) {
		for (int i = 1; i <= n; ++i) {
			for (int j = 1; j <= n; ++j) {
				val[i][j] = max (val[i][j], val[i][k] + val[k][j]);
			}
		}
	}
	for (int i = 1; i <= n; ++i) {
		if (val[i][i] >= 0) {
			return 1;
		}
	}
	return 0;
}
 
 
 
int main () {
//	freopen ("input.txt", "r", stdin);
	cin >> n >> m >> d;
	for (int i = 1; i <= n; ++i) {
		for (int j = 1; j <= d; ++j) {
			cin >> buy[i][j] >> sell[i][j];
		}
	}
	for (int i = 1; i <= n; ++i) {
		for (int j = 1; j <= n; ++j) {
			dis[i][j] = INF;
			if (i == j) dis[i][j] = 0;
		}
	}
	for (int i = 1; i <= m; ++i) {
		int l, r, w;
		cin >> l >> r >> w;
		dis[l][r] = w;
	}
	for (int k = 1; k <= n; ++k) {
		for (int i = 1; i <= n; ++i) {
			for (int j = 1; j <= n; ++j) {
				dis[i][j] = min (dis[i][j], dis[i][k] + dis[k][j]);
			}
		}
	} 
	for (int i = 1; i <= n; ++i) {
		for (int j = 1; j <= n; ++j) {
			if (i == j) continue;
			for (int k = 1; k <= d; ++k) {
				// k-th item-y i-njiden satyn alyan j-nynjyda satyan
				if (sell[j][k] != -1 and buy[i][k] != -1) profit[i][j] = max (profit[i][j], sell[j][k] - 0LL - buy[i][k]);
			}
		}
	}
	ll l = 1, r = INF, jog = 0;
	while (l <= r) {
		int md = (l + r) / 2;
		if (check (md)) {
			jog = md;
			l = md + 1;
		}
		else {
			r = md - 1;
		}
	}
	cout << jog;
}

• Subtask 1: 12 / 12
• Subtask 2: 21 / 21
• Subtask 3: 33 / 33
• Subtask 4: 34 / 34