Cod sursa(job #693410)

Utilizator alexdmotocMotoc Alexandru alexdmotoc Data 27 februarie 2012 12:24:16
Problema Ciclu hamiltonian de cost minim Scor 5
Compilator cpp Status done
Runda Arhiva educationala Marime 1.38 kb
#include <cstdio>
#include <vector>
#include <iostream>
#include <cstring>

using namespace std;

#define PB push_back
#define MKP make_pair
#define INF 0x3f3f3f3f

int N , M , costuri[20][20] , minim;
bool viz[20];

vector <pair <int , int> > lista[20];

int sir[20] , dim;

void get_min ()
{
	int cost = costuri[sir[N]][sir[1]];
	
	for (int i = 1 ; i < N ; ++i)
	{
		int nod1 = sir[i];
		int nod2 = sir[i + 1];
		int costcur = costuri[nod1][nod2];
		
		cost += costcur;
	}
	
	if (cost < minim)
		minim = cost;
}


void dfs (int nod)
{
	if (viz[nod]) return;
	
	viz[nod] = true;
	sir[++dim] = nod;
	
	if (dim == N)
	{
		get_min ();
		return;
	}
	
	
	for (unsigned int i = 0 ; i < lista[nod].size () ; ++i)
	{
		int nodcur = lista[nod][i].first;
		
		if (viz[nodcur]) continue;
		
		dfs (nodcur);
	}
	
	//--dim;
	
}


int main ()
{
	freopen ("hamilton.in" , "r" , stdin);
	freopen ("hamilton.out" , "w" , stdout);
	
	scanf ("%d %d" , &N , &M);
	
	
	int a , b , c;
	
	for (int i = 1 ; i <= M ; ++i)
	{
		scanf ("%d %d %d" , &a , &b , &c);
		
		lista[a].PB (MKP (b , c));
		costuri[a][b] = c;
	}
	
	
	minim = INF;
	
	
	for (int i = 1 ; i <= N ; ++i)
	{
		memset (viz , 0 , sizeof (viz));
		
		dfs (i);
	}
	
	
	if (minim == INF)
		printf ("Nu exista solutie");
	
	else printf ("%d" , minim);
	
	
	return 0;
}