Submission #1041888

#	Time	Username	Problem	Language	Result	Execution time	Memory
1041888		Halym2007	Swapping Cities (APIO20_swap)	C++17	0 / 100	2070 ms	17376 KiB

swap

#include<bits/stdc++.h>
//#include "swap.h"
using namespace std;
#define pb push_back
#define ff first
#define ss second
#define sz size()
#define pii pair <int, int>
const int N = 2e5 + 5;
vector <int> V, U, W, belle, belle1, yol;
int n, m, mx, mx1;

int a1, a2;
vector <pii> v[N];
int vis[N], vis1[N], vis2[N];
bool tt = 0;

void dfs (int x) {
	if (tt) return;
	vis[x] = 1;
	yol.pb (x);
	if (x == a2 and belle.empty()) {
		belle = yol;
		return;
	}
	for (pii i : v[x]) {
		if (vis[x]) continue;
		if (tt) return;
		mx = max (i.ss, mx);
		dfs (i.ff);
		if (tt) return;
	}
	yol.pop_back();
} 



void dfs1 (int x) {
	if (tt) return;
	vis1[x] = 1;
	yol.pb (x);
	if (x == a2 and belle1.empty()) {
		belle1 = yol;
		return;
	}
	for (pii i : v[x]) {
		if (vis1[x]) continue;
		if (tt) return;
		mx1 = max (i.ss, mx1);
		dfs1 (i.ff);
		if (tt) return;
	}
	yol.pop_back();
} 


void init(int N, int M, vector<int> U1, vector<int> V1, vector<int> W1) {
	n = N;m = M;V = V1;U = U1, W = W1;
	for (int i = 0; i < m; ++i) {
		v[U[i]].pb ({V[i], W[i]});
		v[V[i]].pb ({U[i], W[i]});
	}
}

int getMinimumFuelCapacity(int X, int Y) {
	int jogap = 2e9;
 	a1 = X;a2 = Y;
 	if (m <= 2) return -1;
	tt = 0;
	belle.clear();
	mx = 0, mx1 = 0;
	belle1.clear();
 	dfs (X);
	for (int i = 0; i < n; ++i) {
		vis[i] = 0;
	}
	for (int i = 0; i < (int)belle.sz; ++i) {
		vis[belle[i]] = 1;
	}
	tt = 0;
	dfs1(X);
	if (mx != 0 and mx1 != 0) jogap = max (mx, mx1);
	for (int i = 0; i < n; ++i) {
		vis1[i] = 0;
	}
	for (int i = 0; i < (int)belle1.sz; ++i) {
		vis1[belle1[i]] = 1;
	}
	int kl = 1e9, kl1 = 1e9;
	for (int i : belle) {
		for (pii j : v[i]) {
			if (vis[j.ff]) continue;
			kl = min (kl, j.ss);
		}
	}
	jogap = min (jogap, kl + mx);
	for (int i : belle1) {
		for (pii j : v[i]) {
			if (vis1[j.ff]) continue;
			kl1 = min (kl1, j.ss);
		}
	}
	jogap = min (jogap, kl1 + mx1);
	
	
	for (int i = 0; i < n; ++i) {
		vis1[i] = vis[i] = 0;;
	}
	
	if (jogap == 1e9) jogap = -1;
	return jogap;
	
}



//#include <cassert>
//#include <cstdio>
//
//#include <string>
//#include <vector>
//
//int main() {
//	freopen ("input.txt", "r", stdin);
//  int N, M;
//  assert(2 == scanf("%d %d", &N, &M));
//  
//  std::vector<int> U(M), V(M), W(M);
//  for (int i = 0; i < M; ++i) {
//    assert(3 == scanf("%d %d %d", &U[i], &V[i], &W[i]));
//  }
//
//  int Q;
//  assert(1 == scanf("%d", &Q));
//
//  std::vector<int> X(Q), Y(Q);
//  for (int i = 0; i < Q; ++i) {
//    assert(2 == scanf("%d %d", &X[i], &Y[i]));
//  }
//
//  init(N, M, U, V, W);
//  
//  std::vector<int> minimum_fuel_capacities(Q);
//  for (int i = 0; i < Q; ++i) {
//    minimum_fuel_capacities[i] = getMinimumFuelCapacity(X[i], Y[i]);
//  }
//
//  for (int i = 0; i < Q; ++i) {
//    printf("%d\n", minimum_fuel_capacities[i]);
//  }
//  
//  return 0;
//}

• Subtask 1: 0 / 6
• Subtask 2: 0 / 7
• Subtask 3: 0 / 17
• Subtask 4: 0 / 20
• Subtask 5: 0 / 23
• Subtask 6: 0 / 27