Cod sursa(job #1534061)

Utilizator andrei.arnautuAndi Arnautu andrei.arnautu Data 23 noiembrie 2015 11:24:40
Problema Ciclu hamiltonian de cost minim Scor 35
Compilator cpp Status done
Runda Arhiva educationala Marime 1.26 kb
#include <cstdio>
#include <algorithm>

using namespace std;

const int MAX_N = 18;
const int MAX_INF = 0x3fffffff;
                 // 0111 1111 1111 1111 1111 1111 1111 1111 == (2^31)-1
const int MIN_INF = 0x80000000;
                 // 1000 0000 0000 0000 0000 0000 0000 0000 == -(2^31)

                 // 1111 1111 1111 1111 1111 1111 1111 1111 == -1
                 // 0000 0000 0000 0000 0000 0000 0000 0001 ==  1

int cost[1 + MAX_N][1 + MAX_N];
int n, m;

bool folosit[1 + MAX_N];

int back(int k, int u) { // k = nr. de noduri din ciclu
  int minim;
  if (k == n+1 && u == 1)
  {
    minim = 0;
  }
  else
  {
    minim = MAX_INF;
    for (int v = 0; v < n; v++)
    {
	   if (!folosit[v] && cost[u][v] > 0)
      {
        folosit[v] = true;
	     minim = min(minim, cost[u][v] + back(k+1, v));
        folosit[v]= false;
      }
    }
  }
  return minim;
}

int main() {
  int i;
  freopen("hamilton.in", "r", stdin);
  freopen("hamilton.out", "w", stdout);
  scanf("%d%d", &n, &m);
  for (i = 0; i < m; i++) {
    int u, v, c;
    scanf("%d%d%d", &u, &v, &c);
    cost[u][v] = c;
  }
  int minim = back(1, 1);

  if (minim == MAX_INF)
    printf("Nu exista solutie");
  else
    printf("%d\n", minim);
  return 0;
}