TheAlgorithms-C/data_structures/graphs/hamiltonian.c

104 lines
3.0 KiB
C

#include <stdbool.h>
#include <stdio.h>
#include "Graph.h"
#define MAX_NODES 1000
bool visited[MAX_NODES];
bool hamiltonR(Graph g, int nV, Vertex v, Vertex dest, int d)
{
// v = current vertex considered
// dest = destination vertex
// d = distance "remaining" until path found
Vertex w;
if (v == dest)
{
return (d == 0);
}
else
{
visited[v] = true;
for (w = 0; w < nV; w++)
{
if (adjacent(g, v, w) && !visited[w])
{
if (hamiltonR(g, nV, w, dest, d - 1))
{
return true;
}
}
}
}
visited[v] = false;
return false;
}
bool hasHamiltonianPath(Graph g, int nV, Vertex src, Vertex dest)
{
Vertex v;
for (v = 0; v < nV; v++) visited[v] = false;
return hamiltonR(g, nV, src, dest, nV - 1);
}
int main(void)
{
Edge e;
int n;
printf("Enter the number of vertices: ");
scanf("%d", &n);
Graph g = newGraph(n);
Vertex src, dest;
printf("Enter source node: ");
scanf("%d", &src);
printf("Enter destination node: ");
scanf("%d", &dest);
printf("Enter an edge (from): ");
while (scanf("%d", &e.v) == 1)
{
printf("Enter an edge (to): ");
scanf("%d", &e.w);
insertEdge(g, e);
printf("Enter an edge (from): ");
}
printf("Finished.\n");
printf("The graph has ");
if (hasHamiltonianPath(g, n, src, dest))
printf("a");
else
printf("no");
printf(" Hamiltonian path from %d to %d.\n", src, dest);
freeGraph(g);
return 0;
}
// By
// .----------------. .----------------. .----------------.
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// | | | | _| | | |_ | || | \ `--' / | | | | |_____| | || | `.__.'
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// |
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// Email : z5261243@unsw.edu.au
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