oj.uz

Submission #124604

# Submission time Handle Problem Language Result Execution time Memory
124604 2019-07-03T14:56:00 Z MoNsTeR_CuBe Sightseeing (NOI14_sightseeing) C++17
25 / 25
 3171 ms 100984 KB 
#include <bits/stdc++.h>
using namespace std;

const int INF = numeric_limits<int>::max();

vector< int > dist;

vector< int > U;

vector< int > taille;

int getParents(int a){
	if(U[a] == a) return a;
	else return U[a] = getParents(U[a]);
}

void Union(int a, int b){
	a = getParents(a);
	b = getParents(b);
	
	if(taille[a] < taille[b]){
		taille[a] += taille[b];
		U[a] = U[b];
	}else{
		taille[b] += taille[a];
		U[b] = U[a];
	}
}

vector< vector< pair<int, int> > > Graph;

vector< bool > visited;

void dfs(int node, int cost){
	dist[node] = cost;
	visited[node] = true;
	for(pair<int, int> p : Graph[node]){
		if(visited[p.first]) continue;
		dfs(p.first, min(cost, p.second));
	}
}

signed main(){
	
	int n, m, q;
	scanf("%d%d%d", &n, &m, &q);
	
	Graph.resize(n+1);
	
	vector< tuple<int, int, int> > edges(m);
	
	for(int i = 0; i < m; i++){
		
		int a, b, c;
		scanf("%d%d%d", &a, &b, &c);
		
		edges[i] = make_tuple(c,a,b);
	}
	
	taille.assign(n+1,1);
	dist.resize(n+1);
	U.resize(n+1);
	
	for(int i = 1; i <= n; i++){
		U[i] = i;
	}
	
	sort(edges.begin(), edges.end(), greater< tuple<int, int, int> >());
	
	for(int i = 0; i < m; i++){
		int a = get<1>(edges[i]);
		int b = get<2>(edges[i]);
		
		int c = get<0>(edges[i]);
		
		if(getParents(a) == getParents(b)){
			continue;
		}
		Union(a,b);
		
		Graph[a].push_back(make_pair(b,c));
		Graph[b].push_back(make_pair(a,c));
	}
	visited.assign(n+1, false);
	dfs(1,INF);
	
	for(int i = 0; i < q; i++){
		int a;
		scanf("%d", &a);
		printf("%d\n", dist[a]);
	}
}

Compilation message

sightseeing.cpp: In function 'int main()':
sightseeing.cpp:46:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d", &n, &m, &q);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~
sightseeing.cpp:55:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d%d", &a, &b, &c);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~
sightseeing.cpp:89:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &a);
   ~~~~~^~~~~~~~~~

Subtask #1
4.0 / 4.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 380 KB Output is correct
2 Correct 2 ms 276 KB Output is correct

Subtask #2
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct

Subtask #3
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 44 ms 3548 KB Output is correct
2 Correct 40 ms 3188 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2214 ms 63488 KB Output is correct
2 Correct 3171 ms 100984 KB Output is correct