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Submission #1069436

# Submission time Handle Problem Language Result Execution time Memory
1069436 2024-08-21T22:34:39 Z pawned Swapping Cities (APIO20_swap) C++17
6 / 100
 2000 ms 26932 KB 
#pragma GCC optimize("O1,O2,O3,Ofast,unroll-loops")

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

#define fi first
#define se second
#define pb push_back
typedef long long ll;
typedef pair<int, int> ii;
typedef vector<int> vi;

#include "swap.h"

const int MAX = 1e5 + 5;

int N, M;

vector<ii> adj[MAX];	// {vertex, dist}

vi wt;

bool checkm(int cut) {	// minimum weight so has tree from 0
	vi adjc[N];
	for (int i = 0; i < N; i++) {
		for (ii p : adj[i]) {
			if (p.se <= cut)
				adjc[i].pb(p.fi);
		}
	}
	vector<bool> vis(N, false);
	queue<int> q;
	q.push(0);
	vis[0] = true;
	while (!q.empty()) {
		int x = q.front();
		q.pop();
		for (int y : adjc[x]) {
			if (!vis[y]) {
				q.push(y);
				vis[y] = true;
			}
		}
	}
	vi adjd[N];
	for (int i = 0; i < N; i++) {
		if (!vis[i])
			continue;
		for (int x : adjc[i]) {
			if (vis[x])
				adjd[i].pb(x);
		}
	}
	for (int i = 0; i < N; i++) {
		if (adjd[i].size() >= 3)
			return true;
	}
	return false;
}

int comp() {
	int low = 0;
	int high = M - 1;
	int ans = -1;	// minimum so can pass
	while (low <= high) {	// false, false, false, true, true, true
		int mid = (low + high) / 2;
		if (checkm(wt[mid])) {
			ans = mid;
			high = mid - 1;
		}
		else {
			low = mid + 1;
		}
	}
	if (ans != -1)
		return wt[ans];
	return -1;
}

int minv;	// minimum so there's a tree

vi maxw(MAX, -1);

void dfs(int n) {
	for (ii p : adj[n]) {
		if (maxw[p.fi] == -1) {
			maxw[p.fi] = max(maxw[n], p.se);
			dfs(p.fi);
		}
	}
}

void init(int N_g, int M_g, vi U_g, vi V_g, vi W_g) {
	N = N_g;
	M = M_g;
	for (int i = 0; i < M; i++) {
		adj[U_g[i]].pb({V_g[i], W_g[i]});
		adj[V_g[i]].pb({U_g[i], W_g[i]});
		wt.pb(W_g[i]);
	}
	sort(wt.begin(), wt.end());
	minv = comp();
	maxw[0] = 0;
	dfs(0);
/*	cout<<"minv: "<<minv<<endl;
	cout<<"maxw: ";
	for (int i = 0; i < N; i++) {
		cout<<maxw[i]<<" ";
	}
	cout<<endl;*/
}

bool check(int cut, int X, int Y) {
	vi adjc[N];
	for (int i = 0; i < N; i++) {
		for (ii p : adj[i]) {
			if (p.se <= cut)
				adjc[i].pb(p.fi);
		}
	}
	vector<bool> vis(N, false);
	queue<int> q;
	q.push(X);
	vis[X] = true;
	while (!q.empty()) {
		int x = q.front();
		q.pop();
		for (int y : adjc[x]) {
			if (!vis[y]) {
				q.push(y);
				vis[y] = true;
			}
		}
	}
	if (!vis[Y])
		return false;
	vi adjd[N];
	for (int i = 0; i < N; i++) {
		if (!vis[i])
			continue;
		for (int x : adjc[i]) {
			if (vis[x])
				adjd[i].pb(x);
		}
	}
	int cnte = 0;	// number of edges
	int sz = 0;	// number of vertices
	for (int i = 0; i < N; i++) {
		cnte += adjd[i].size();
		if (adjd[i].size() >= 1)
			sz++;
	}
	cnte /= 2;
//	cout<<"sz, cnte: "<<sz<<" "<<cnte<<endl;
	if (cnte > sz - 1)	// has a cycle
		return true;
	for (int i = 0; i < N; i++) {
		if (adjd[i].size() >= 3)
			return true;
	}
	return false;
}

int getMinimumFuelCapacity(int X, int Y) {
	if (M == N)
		return wt[M - 1];
	if (minv == -1)
		return -1;
	int low = 0;
	int high = M - 1;
	int ans = -1;	// minimum so can pass
	while (low <= high) {	// false, false, false, true, true, true
		int mid = (low + high) / 2;
		if (check(wt[mid], X, Y)) {
			ans = mid;
			high = mid - 1;
		}
		else {
			low = mid + 1;
		}
	}
	if (ans != -1)
		return max(minv, ans);
	return -1;
}

Subtask #1
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 3160 KB Output is correct
2 Correct 1 ms 3164 KB Output is correct
3 Correct 1 ms 3164 KB Output is correct
4 Correct 2 ms 3164 KB Output is correct
5 Correct 2 ms 3164 KB Output is correct
6 Correct 2 ms 3164 KB Output is correct
7 Correct 2 ms 3164 KB Output is correct
8 Correct 2 ms 3164 KB Output is correct
9 Correct 135 ms 18000 KB Output is correct
10 Correct 155 ms 21200 KB Output is correct
11 Correct 152 ms 20936 KB Output is correct
12 Correct 166 ms 21984 KB Output is correct
13 Correct 231 ms 21964 KB Output is correct
14 Correct 130 ms 18260 KB Output is correct
15 Correct 192 ms 25076 KB Output is correct
16 Correct 192 ms 24520 KB Output is correct
17 Correct 228 ms 25824 KB Output is correct
18 Correct 268 ms 25800 KB Output is correct
19 Correct 49 ms 11092 KB Output is correct
20 Correct 212 ms 25796 KB Output is correct
21 Correct 193 ms 25224 KB Output is correct
22 Correct 205 ms 26676 KB Output is correct
23 Correct 276 ms 26932 KB Output is correct

Subtask #2
0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 3160 KB Output is correct
2 Correct 1 ms 3164 KB Output is correct
3 Execution timed out 2071 ms 25376 KB Time limit exceeded
4 Halted 0 ms 0 KB -

Subtask #3
0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 3160 KB Output is correct
2 Correct 1 ms 3164 KB Output is correct
3 Correct 1 ms 3164 KB Output is correct
4 Correct 2 ms 3164 KB Output is correct
5 Correct 2 ms 3164 KB Output is correct
6 Correct 2 ms 3164 KB Output is correct
7 Correct 2 ms 3164 KB Output is correct
8 Correct 2 ms 3164 KB Output is correct
9 Incorrect 1 ms 3164 KB Output isn't correct
10 Halted 0 ms 0 KB -

Subtask #4
0 / 20.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 3164 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 3160 KB Output is correct
2 Correct 1 ms 3164 KB Output is correct
3 Correct 1 ms 3164 KB Output is correct
4 Correct 2 ms 3164 KB Output is correct
5 Correct 2 ms 3164 KB Output is correct
6 Correct 2 ms 3164 KB Output is correct
7 Correct 2 ms 3164 KB Output is correct
8 Correct 2 ms 3164 KB Output is correct
9 Correct 135 ms 18000 KB Output is correct
10 Correct 155 ms 21200 KB Output is correct
11 Correct 152 ms 20936 KB Output is correct
12 Correct 166 ms 21984 KB Output is correct
13 Correct 231 ms 21964 KB Output is correct
14 Correct 130 ms 18260 KB Output is correct
15 Correct 192 ms 25076 KB Output is correct
16 Correct 192 ms 24520 KB Output is correct
17 Correct 228 ms 25824 KB Output is correct
18 Correct 268 ms 25800 KB Output is correct
19 Execution timed out 2071 ms 25376 KB Time limit exceeded
20 Halted 0 ms 0 KB -

Subtask #6
0 / 27.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 3164 KB Output isn't correct
2 Halted 0 ms 0 KB -