oj.uz

Submission #45068

# Submission time Handle Problem Language Result Execution time Memory
45068 2018-04-11T06:26:48 Z nibnalin Cities (BOI16_cities) C++17
0 / 100
 1205 ms 40480 KB 
#include <iostream>
#include <cstdio>
#include <vector>
#include <set>
using namespace std;

const int maxn = int(1e5)+5, maxk = 6, inf = int(1e9)+5;

int n, D[maxk][maxn], dp[(1<<maxk)][maxn], A[maxk];
vector<pair<int, int>> graph[maxn];

void dijkstra(int type, int node)
{
	for(int i = 0;i < n;i++) D[type][i] = inf;
	D[type][node] = 0;

	set<pair<int, int>> Q;
	Q.insert({D[type][node], node});

	while(!Q.empty())
	{
		pair<int, int> top = *Q.begin();
		Q.erase(Q.begin());

		for(auto it: graph[top.second])
		{
			if(D[type][it.first] > D[type][top.second]+it.second)
			{
				if(D[type][it.first] != inf) Q.erase({D[type][it.first], it.first});
				D[type][it.first] = D[type][top.second]+it.second;
				Q.insert({D[type][it.first], it.first});
			}
		}
	}
}

int main(void)
{
	int k, m, u, v, w;
	scanf("%d%d%d", &n, &k, &m);
	for(int i = 0;i < k;i++)
	{
		scanf("%d", &A[i]);
		A[i]--;
	}

	for(int i = 0;i < m;i++)
	{
		scanf("%d%d%d", &u, &v, &w);
		u--, v--;
		graph[u].push_back({v, w}), graph[v].push_back({u, w});
	}

	for(int i = 0;i < k;i++) dijkstra(i, A[i]);

	for(int mask = 1;mask < (1<<k);mask++)
	{
		set<pair<int, int>> Q;
		for(int i = 0;i < n;i++)
		{
			dp[mask][i] = inf;
			for(int j = 0;j < k;j++)
			{
				if((mask&(1<<j))) dp[mask][i] = min(dp[mask][i], dp[(mask^(1<<j))][i]+D[j][i]);
			}
			Q.insert({dp[mask][i], i});
		}

		while(!Q.empty())
		{
			pair<int, int> top = *Q.begin();
			Q.erase(Q.begin());

			for(auto it: graph[top.second])
			{
				if(dp[mask][it.first] > dp[mask][top.second]+it.second)
				{
					Q.erase({dp[mask][it.first], it.first});
					dp[mask][it.first] = dp[mask][top.second]+it.second;
					Q.insert({dp[mask][it.first], it.first});
				}
			}
		}
	}

	int res = inf;
	for(int i = 0;i < n;i++) res = min(res, dp[(1<<k)-1][i]);
	printf("%d\n", res);
}

Compilation message

cities.cpp: In function 'int main()':
cities.cpp:40:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d", &n, &k, &m);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~
cities.cpp:43:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &A[i]);
   ~~~~~^~~~~~~~~~~~~
cities.cpp:49:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d%d", &u, &v, &w);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~

Subtask #1
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 2680 KB Output is correct
2 Correct 4 ms 2792 KB Output is correct
3 Incorrect 3 ms 2792 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #2
0 / 14.0

# Verdict Execution time Memory Grader output
1 Incorrect 421 ms 21800 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Incorrect 7 ms 21800 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 23.0

# Verdict Execution time Memory Grader output
1 Incorrect 664 ms 29868 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
0 / 26.0

# Verdict Execution time Memory Grader output
1 Incorrect 1205 ms 40480 KB Output isn't correct
2 Halted 0 ms 0 KB -