Implementation of the Minimum Spanning Tree Prim algorithm (using adjacent table Storage) C ++

 

// Implement the Prim algorithm (using the adjacent table Storage). cpp: Defines the entry point for the console application.

//

# Include "stdafx. h"

# Include "stdafx. h"

# Include <iostream>

# Deprecision MAX 100

# Define Infinity 65535

Typedef int WeiType;

Using namespace std;

Struct edgeNode

{

Int no; // edge serial number

Char info; // edge name

WeiType weight; // Edge weight

Struct edgeNode * next; // next

};

Struct vexNode

{

Char info; // node name

Struct edgeNode * link; // endpoint connected to it

};

// Store node Information

VexNode adjlist [MAX];

// Access flag

Bool visited [MAX];

// Lowcost [j] minimum cost of storage from Start Node to node j

WeiType lowcost [MAX];

// Parent [j] indicates the precursor node of node j.

Int parent [MAX];

// Create an adjacent table Storage

Void createGraph (vexNode * adjlist, const int n, const int e, const int v0)

{

 

Int I;

For (I = 1; I <= n; I ++)

{

Cout <"Enter the node" <I <"name :";

Cin> adjlist [I]. info;

Adjlist [I]. link = NULL;

// Initialization

Visited [I] = false;

Lowcost [I] = Infinity;

Parent [I] = v0;

}

EdgeNode * p1, * p2;

Int v1, v2;

WeiType weight;

For (I = 1; I <= e; I ++)

{

Cout <"enter the second-end node number of Edge" <I <:";

Cin> v1> v2;

Cout <"weight of this edge :";

Cin> weight;

P1 = (edgeNode *) malloc (sizeof (edgeNode ));

P2 = (edgeNode *) malloc (sizeof (edgeNode ));

P1-> no = v1;

P1-> weight = weight;

P1-> info = adjlist [v1]. info;

P1-> next = adjlist [v2]. link;

Adjlist [v2]. link = p1;

P2-> no = v2;

P2-> weight = weight;

P2-> info = adjlist [v2]. info;

P2-> next = adjlist [v1]. link;

Adjlist [v1]. link = p2;

}

}

 

Int _ tmain (int argc, _ TCHAR * argv [])

{

Int cases;

Cout <"Enter the number of cases :";

Cin> cases;

While (cases --)

{

Int n, e;

Cout <"Enter the number of nodes :";

Cin> n;

Cout <"Enter the number of sides :";

Cin> e;

Cout <"start from which node :";

Int v;

Cin> v;

Int I, j;

// Sum of the weights of the Minimum Spanning Tree

WeiType sum = 0;

CreateGraph (adjlist, n, e, v );

EdgeNode * p, * q;

P = adjlist [v]. link;

Visited [v] = true;

While (p! = NULL)

{

Lowcost [p-> no] = p-> weight;

P = p-> next;

}

WeiType minCost;

For (I = 1; I <n; I ++)

{

MinCost = Infinity;

Int k;

For (j = 1; j <= n; j ++)

{

If (minCost> lowcost [j] &! Visited [j])

{

MinCost = lowcost [j];

K = j;

}

}

Sum + = minCost;

Visited [k] = true;

Q = adjlist [k]. link;

While (q! = NULL)

{

If (! Visited [q-> no] & q-> weight <lowcost [q-> no])

{

Lowcost [q-> no] = q-> weight;

Parent [q-> no] = k;

}

Q = q-> next;

}

}

Cout <"the edge set of the Minimum Spanning Tree is:" <endl;

For (I = 1; I <= n; I ++)

If (I! = V)

Cout <"(" <adjlist [parent [I]. info <"," <adjlist [I]. info <")" <"";

Cout <endl;

Cout <"Minimum Spanning Tree weight:" <sum <endl;

}

System ("pause ");

Return 0;

}

----------------------------------------------------- Program test --------------------------------------------------

 

Enter the number of cases: 1

Enter the number of nodes: 9

Enter the number of edges: 14

Enter the Start Node: 2

Enter the name of Node 1:

Enter Node 2 Name: B

Enter Node 3 name: c

Enter node 4 name: d

Enter node 5 Name: e

Enter the name of node 6: f

Enter the name of node 7: g

Enter node 8 name: h

Enter node 9 name: I

Enter the node number at the second end of edge 1: 1 2

Edge Weight: 4

Enter the node number at the second end of edge 2: 1 8

Edge Weight: 8

Enter the node number at the second end of edge 3: 2 3

Edge Weight: 8

Enter the node number at the second end of edge 4: 2 8

Weight of this edge: 11

Enter the node number at the second end of edge 5: 3 4

Edge Weight: 7

Enter the node number at the second end of edge 6: 3 6

Edge Weight: 4

Enter the node number at the second end of edge 7: 3 9

Weight of this edge: 2

Enter the node number at the second end of edge 8: 4 5

Weight of this edge: 9

Enter the node number at the second end of edge 9: 4 6

Weight of this edge: 14

Enter the node number at the second end of edge 10: 5 6

Weight of this edge: 10

Enter the node number of the second end of edge 11: 6 7

Weight of this edge: 2

Enter the node number at the second end of edge 12: 7 8

Weight of this edge: 1

Enter the node number of the second end of edge 13: 7 9

Weight of this edge: 6

Enter the node number at the second end of edge 14: 8 9

Edge Weight: 7

The edge set of the Minimum Spanning Tree is:

(B, a) (B, c) (c, d) (d, e) (c, f) (f, g) (g, h) (c, I)

Minimum Spanning Tree weight: 37

Press any key to continue...

 

 

Author heyongluoyao8