oj.uz

답안 #57078

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
57078 2018-07-13T20:03:26 Z IvanC Cities (BOI16_cities) C++17
74 / 100
 6000 ms 126644 KB 
#include <bits/stdc++.h>
using namespace std;
 
typedef long long ll;
typedef pair<ll,ll> ii;
typedef tuple<ll,int,int> trinca;
 
const int MAXN = 1e5 + 10;
const int MAXK = 7;
const int MAXL = 35;
const ll INF = 1e18;
 
vector<ii> grafo[MAXN]; 
ll matriz[MAXN][MAXK],menor_distancia[MAXN][MAXL];
int N,K,M,qual[MAXK],processado[MAXN];
int jafoi[MAXN][MAXL];
 
void Dijkstra(int idx){
	memset(processado,0,sizeof(processado));
	priority_queue<ii, vector<ii> , greater<ii> > pq;
	pq.push(ii(0,qual[idx]));
	while(!pq.empty()){
		ii davez = pq.top();
		pq.pop();
		int v = davez.second;
		ll path = davez.first;
		if(processado[v]) continue;
		processado[v] = 1;
		matriz[v][idx] = path;
		for(ii aresta : grafo[v]){
			int u = aresta.first;
			ll w = aresta.second;
			if(!processado[u]) pq.push(ii(path + w,u));
		}
	}
}
 
int main(){
	scanf("%d %d %d",&N,&K,&M);
	for(int i = 0;i<K;i++){
		scanf("%d",&qual[i]);
	}
	for(int i = 1;i<=M;i++){
		int u,v,w;
		scanf("%d %d %d",&u,&v,&w);
		grafo[u].push_back(ii(v,w));
		grafo[v].push_back(ii(u,w));
	}
	for(int i = 0;i<K;i++) Dijkstra(i);
	priority_queue<trinca,vector<trinca>, greater<trinca> > pq;
	int alvo = (1 << K) - 1;
	for(int i = 1;i<=N;i++){
		for(int bitmask = 0;bitmask <= alvo;bitmask++){
			menor_distancia[i][bitmask] = INF;
		}
	}
	for(int i = 0;i<K;i++){
		pq.push(make_tuple(0,(1 << i),qual[i]));
	}
	ll ubound = INF;
	for(int i = 1;i<=N;i++){
		ll candidato = 0;
		for(int k = 0;k<K;k++){
			candidato += matriz[i][k];
		}
		ubound = min(ubound,candidato);
	}
	while(!pq.empty()){
		trinca davez = pq.top();
		pq.pop();
		ll path = get<0>(davez);
		int bitmask = get<1>(davez), v = get<2>(davez);
		if(jafoi[v][bitmask]) continue;
		jafoi[v][bitmask] = 1;
		if(bitmask == alvo){
			printf("%lld\n",path);
			return 0;
		}
		for(int i = 0;i<K;i++){
			if(bitmask & (1 << i)) continue;
			int mascara = bitmask | (1 << i);
			ll w = matriz[v][i];
			if(path + w > ubound) continue;
			if(path + w < menor_distancia[v][mascara]){
				menor_distancia[v][mascara] = path + w;
				pq.push(make_tuple(path + matriz[v][i],mascara, v ));
			}
		}
		for(ii aresta : grafo[v]){
			int u = aresta.first;
			ll w = aresta.second;
			if(path + w > ubound) continue;
			if(path + w < menor_distancia[u][bitmask]){
				menor_distancia[u][bitmask] = path + w;
				pq.push(make_tuple(path + w,bitmask,u));
			}
		}
	}
	
	return 0;
	
}

Compilation message

cities.cpp: In function 'int main()':
cities.cpp:39:7: 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:41:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&qual[i]);
   ~~~~~^~~~~~~~~~~~~~~
cities.cpp:45:8: 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
22.0 / 22.0

# 결과 실행 시간 메모리 Grader output
1 Correct 5 ms 3064 KB Output is correct
2 Correct 5 ms 3180 KB Output is correct
3 Correct 4 ms 3232 KB Output is correct
4 Correct 4 ms 3232 KB Output is correct
5 Correct 6 ms 3232 KB Output is correct

Subtask #2
14.0 / 14.0

# 결과 실행 시간 메모리 Grader output
1 Correct 880 ms 66412 KB Output is correct
2 Correct 1077 ms 67724 KB Output is correct
3 Correct 431 ms 67724 KB Output is correct
4 Correct 307 ms 67724 KB Output is correct
5 Correct 648 ms 67724 KB Output is correct
6 Correct 280 ms 67724 KB Output is correct
7 Correct 9 ms 67724 KB Output is correct
8 Correct 8 ms 67724 KB Output is correct

Subtask #3
15.0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 13 ms 67724 KB Output is correct
2 Correct 12 ms 67724 KB Output is correct
3 Correct 9 ms 67724 KB Output is correct
4 Correct 9 ms 67724 KB Output is correct

Subtask #4
23.0 / 23.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2582 ms 77228 KB Output is correct
2 Correct 1990 ms 77228 KB Output is correct
3 Correct 1300 ms 77228 KB Output is correct
4 Correct 1350 ms 77228 KB Output is correct
5 Correct 418 ms 77228 KB Output is correct
6 Correct 402 ms 77228 KB Output is correct

Subtask #5
0 / 26.0

# 결과 실행 시간 메모리 Grader output
1 Execution timed out 6038 ms 126644 KB Time limit exceeded
2 Halted 0 ms 0 KB -